138 |
138 |
139 \begin{frame} |
139 \begin{frame} |
140 \maketitle |
140 \maketitle |
141 \end{frame} |
141 \end{frame} |
142 |
142 |
143 \section{Tests: Getting started} |
143 \begin{frame} |
144 \begin{frame}[fragile] |
144 \frametitle{Outline} |
145 \frametitle{gcd revisited!} |
145 \tableofcontents |
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146 % You might wish to add the option [pausesections] |
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147 \end{frame} |
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148 |
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149 \section{3D Data Visualization} |
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150 |
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151 \begin{frame} |
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152 \frametitle{What is visualization?} |
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153 \Large |
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154 \begin{center} |
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155 Visual representation of data |
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156 \end{center} |
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157 \end{frame} |
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158 |
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159 |
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160 %% \begin{frame} |
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161 %% \frametitle{Is this new?} |
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162 %% \begin{center} |
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163 %% We have moved from: |
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164 %% \end{center} |
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165 %% \begin{columns} |
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166 %% \column{} |
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167 %% \hspace*{-1in} |
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168 %% \includegraphics[width=1.75in,height=1.75in, interpolate=true]{data/3832} |
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169 %% \column{}\hspace*{-0.25in} |
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170 %% To |
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171 %% \column{} |
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172 %% \hspace*{-1in} |
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173 %% \includegraphics[width=1.75in, height=1.75in, interpolate=true]{data/torus} |
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174 %% \end{columns} |
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175 %% \end{frame} |
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176 |
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177 \begin{frame} |
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178 \frametitle{3D visualization} |
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179 \Large |
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180 \begin{center} |
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181 Harder but important |
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182 \end{center} |
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183 \end{frame} |
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184 |
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185 \begin{frame} |
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186 \frametitle{Is this Graphics?} |
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187 \Large |
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188 \begin{center} |
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189 Visualization is about data! |
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190 \end{center} |
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191 \end{frame} |
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192 |
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193 \begin{frame} |
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194 \frametitle{Examples: trajectory in space} |
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195 \Large |
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196 \begin{center} |
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197 \pgfimage[width=2.5in]{MEDIA/m2/mlab/plot3d_ex} |
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198 \end{center} |
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199 \end{frame} |
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200 |
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201 \begin{frame} |
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202 \frametitle{Examples: Fire in a room} |
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203 \Large |
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204 \begin{center} |
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205 Demo of data |
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206 \end{center} |
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207 \inctime{10} |
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208 \end{frame} |
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209 |
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210 \section{Tools available} |
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211 |
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212 \subsection{mlab} |
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213 |
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214 \begin{frame} |
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215 {Overview} |
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216 \Large |
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217 \begin{itemize} |
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218 \item Simple |
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219 \item Convenient |
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220 \item Full-featured |
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221 \end{itemize} |
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222 \end{frame} |
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223 |
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224 \begin{frame}[fragile] |
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225 |
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226 \frametitle{Getting started} |
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227 \myemph{\Large Vanilla:} |
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228 \begin{lstlisting}[language=bash] |
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229 $ ipython -wthread |
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230 \end{lstlisting} |
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231 \myemph{\Large with Pylab:} |
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232 \begin{lstlisting}[language=bash] |
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233 $ ipython -pylab -wthread |
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234 \end{lstlisting} |
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235 \end{frame} |
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236 |
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237 \begin{frame}[fragile] |
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238 \frametitle{Using mlab} |
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239 |
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240 \begin{lstlisting} |
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241 In []:from enthought.mayavi import mlab |
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242 \end{lstlisting} |
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243 |
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244 \vspace*{0.5in} |
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245 |
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246 \myemph{\Large Try these} |
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247 |
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248 \vspace*{0.25in} |
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249 |
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250 \begin{lstlisting} |
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251 In []: mlab.test_<TAB> |
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252 In []: mlab.test_contour3d() |
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253 In []: mlab.test_contour3d?? |
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254 \end{lstlisting} |
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255 \end{frame} |
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256 |
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257 \begin{frame} |
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258 {Exploring the view} |
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259 \begin{columns} |
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260 \column{0.6\textwidth} |
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261 \pgfimage[width=3in]{MEDIA/m2/contour3d} |
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262 \column{0.4\textwidth} |
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263 \begin{itemize} |
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264 \item Mouse |
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265 \item Keyboard |
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266 \item Toolbar |
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267 \item Mayavi icon\pgfimage[width=0.2in]{MEDIA/m2/m2_icon} |
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268 \end{itemize} |
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269 \end{columns} |
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270 \end{frame} |
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271 |
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272 \begin{frame}[fragile] |
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273 \frametitle{\mlab\ plotting functions} |
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274 \begin{columns} |
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275 \column{0.25\textwidth} |
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276 \myemph{\Large 0D data} |
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277 \column{0.5\textwidth} |
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278 \pgfimage[width=2in]{MEDIA/m2/mlab/points3d_ex} |
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279 \end{columns} |
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280 |
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281 \begin{lstlisting} |
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282 In []: t = linspace(0, 2*pi, 50) |
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283 In []: u = cos(t) * pi |
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284 In []: x, y, z = sin(u), cos(u), sin(t) |
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285 \end{lstlisting} |
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286 \emphbar{\PythonCode{In []: mlab.points3d(x, y, z)}} |
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287 \end{frame} |
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288 |
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289 \begin{frame} |
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290 \begin{columns} |
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291 \column{0.25\textwidth} |
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292 \myemph{\Large 1D data} |
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293 \column{0.5\textwidth} |
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294 \pgfimage[width=2.5in]{MEDIA/m2/mlab/plot3d_ex} |
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295 \end{columns} |
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296 \emphbar{\PythonCode{In []: mlab.plot3d(x, y, z, t)}} |
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297 |
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298 Plots lines between the points |
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299 |
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300 \end{frame} |
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301 |
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302 \begin{frame}[fragile] |
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303 \begin{columns} |
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304 \column{0.25\textwidth} |
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305 \myemph{\Large 2D data} |
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306 \column{0.5\textwidth} |
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307 \pgfimage[width=2in]{MEDIA/m2/mlab/surf_ex} |
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308 \end{columns} |
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309 \begin{lstlisting} |
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310 In []: x, y = mgrid[-3:3:100j,-3:3:100j] |
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311 In []: z = sin(x*x + y*y) |
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312 \end{lstlisting} |
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313 |
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314 \emphbar{\PythonCode{In []: mlab.surf(x, y, z)}} |
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315 |
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316 \alert{Assumes the points are rectilinear} |
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317 |
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318 \end{frame} |
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319 |
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320 \begin{frame}[fragile] |
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321 \frametitle{mgrid} |
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322 \begin{lstlisting} |
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323 In []: mgrid[0:3,0:3] |
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324 Out[]: |
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325 array([[[0, 0, 0], |
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326 [1, 1, 1], |
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327 [2, 2, 2]], |
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328 |
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329 [[0, 1, 2], |
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330 [0, 1, 2], |
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331 [0, 1, 2]]]) |
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332 |
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333 In []: mgrid[-1:1:5j] |
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334 Out[]: array([-1., -0.5, 0., 0.5, 1.]) |
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335 \end{lstlisting} |
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336 \end{frame} |
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337 |
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338 \begin{frame}[fragile] |
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339 \frametitle{Example} |
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340 \begin{lstlisting} |
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341 In []: x, y = mgrid[-1:1:5j, -1:1:5j] |
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342 In []: z = x*x + y*y |
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343 |
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344 In []: z |
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345 Out[]: |
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346 array([[ 2. , 1.25, 1. , 1.25, 2. ], |
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347 [ 1.25, 0.5 , 0.25, 0.5 , 1.25], |
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348 [ 1. , 0.25, 0. , 0.25, 1. ], |
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349 [ 1.25, 0.5 , 0.25, 0.5 , 1.25], |
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350 [ 2. , 1.25, 1. , 1.25, 2. ]]) |
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351 \end{lstlisting} |
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352 \end{frame} |
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353 |
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354 \begin{frame}[fragile] |
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355 \myemph{\Large 2D data: \texttt{mlab.mesh}} |
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356 \vspace*{0.25in} |
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357 |
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358 \emphbar{\PythonCode{In []: mlab.mesh(x, y, z)}} |
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359 |
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360 \alert{Points needn't be regular} |
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361 |
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362 \vspace*{0.25in} |
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363 \begin{lstlisting} |
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364 In []: phi, theta = mgrid[0:pi:20j, |
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365 ... 0:2*pi:20j] |
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366 In []: x = sin(phi)*cos(theta) |
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367 In []: y = sin(phi)*sin(theta) |
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368 In []: z = cos(phi) |
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369 In []: mlab.mesh(x, y, z, |
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370 ... representation= |
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371 ... 'wireframe') |
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372 \end{lstlisting} |
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373 |
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374 \end{frame} |
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375 |
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376 \begin{frame}[fragile] |
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377 |
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378 \begin{columns} |
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379 \column{0.25\textwidth} |
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380 \myemph{\Large 3D data} |
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381 \column{0.5\textwidth} |
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382 \pgfimage[width=1.5in]{MEDIA/m2/mlab/contour3d}\\ |
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383 \end{columns} |
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384 \begin{lstlisting} |
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385 In []: x, y, z = mgrid[-5:5:64j, |
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386 ... -5:5:64j, |
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387 ... -5:5:64j] |
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388 In []: mlab.contour3d(x*x*0.5 + y*y + |
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389 z*z*2) |
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390 \end{lstlisting} |
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391 \end{frame} |
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392 |
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393 \begin{frame}[fragile] |
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394 |
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395 \myemph{\Large 3D vector data: \PythonCode{mlab.quiver3d}} |
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396 \vspace*{0.25in} |
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397 |
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398 \pgfimage[width=2in]{MEDIA/m2/mlab/quiver3d_ex}\\ |
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399 |
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400 \begin{lstlisting} |
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401 In []: mlab.test_quiver3d() |
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402 \end{lstlisting} |
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403 |
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404 \emphbar{\PythonCode{obj = mlab.quiver3d(x, y, z, u, v, w)}} |
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405 \inctime{20} |
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406 \end{frame} |
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407 |
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408 |
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409 \subsection{Mayavi2} |
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410 |
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411 \begin{frame} |
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412 \frametitle{Introduction to Mayavi} |
146 \begin{itemize} |
413 \begin{itemize} |
147 \item Open gcd.py |
414 \item Most scientists not interested in details of visualization |
148 \end{itemize} |
415 \item Visualization of data files with a nice UI |
149 \begin{lstlisting} |
416 \item Interactive visualization of data (think Matlab) |
150 def gcd(a, b): |
417 \item Embedding visualizations in applications |
151 if a % b == 0: |
418 \item Customization |
152 return b |
419 \end{itemize} |
153 return gcd(b, a%b) |
420 \pause |
154 |
421 \begin{block}{The Goal} |
155 print gcd(15, 65) |
422 Provide a \alert{flexible} library/app for all of these needs! |
156 print gcd(16, 76) |
423 \end{block} |
157 \end{lstlisting} |
424 \end{frame} |
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425 |
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426 \begin{frame} |
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427 {Overview of features} |
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428 \vspace*{-0.3in} |
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429 \begin{center} |
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430 \hspace*{-0.2in}\pgfimage[width=5in]{MEDIA/m2/m2_app3_3} |
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431 \end{center} |
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432 \end{frame} |
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433 |
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434 |
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435 \begin{frame} |
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436 \frametitle{Mayavi in applications} |
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437 \vspace*{-0.3in} |
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438 \begin{center} |
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439 \hspace*{-0.2in}\pgfimage[width=4.5in]{MEDIA/m2/m2_envisage} |
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440 \end{center} |
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441 \end{frame} |
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442 |
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443 \begin{frame} |
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444 \frametitle{Live in your dialogs} |
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445 \vspace*{0.1in} |
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446 \begin{center} |
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447 \hspace*{-0.2in}\pgfimage[width=2.5in]{MEDIA/m2/mlab_tui} |
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448 \end{center} |
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449 \end{frame} |
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450 |
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451 \begin{frame} |
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452 {Exploring the documentation} |
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453 \begin{center} |
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454 \pgfimage[width=4in]{MEDIA/m2/m2_ug_doc} |
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455 \end{center} |
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456 \end{frame} |
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457 |
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458 |
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459 \begin{frame} |
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460 \frametitle{Summary} |
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461 \begin{itemize} |
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462 \item \url{http://code.enthought.com/projects/mayavi} |
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463 \item Uses VTK (\url{www.vtk.org}) |
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464 \item BSD license |
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465 \item Linux, win32 and Mac OS X |
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466 \item Highly scriptable |
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467 \item Embed in Traits UIs (wxPython and PyQt4) |
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468 \item Envisage Plugins |
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469 \item Debian/Ubuntu/Fedora |
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470 \item \alert{Pythonic} |
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471 \end{itemize} |
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472 |
|
473 \inctime{10} |
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474 |
|
475 \end{frame} |
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476 |
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477 \begin{frame} |
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478 {Getting hands dirty!} |
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479 |
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480 \begin{block}{Motivational problem} |
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481 Atmospheric data of temperature over the surface of the earth. |
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482 Let temperature ($T$) vary linearly with height ($z$): |
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483 \begin{center} |
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484 $T = 288.15 - 6.5z$ |
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485 \end{center} |
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486 \end{block} |
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487 \end{frame} |
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488 |
|
489 \begin{frame}[fragile] |
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490 \frametitle{Simple solution} |
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491 |
|
492 \begin{lstlisting} |
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493 lat = linspace(-89, 89, 37) |
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494 lon = linspace(0, 360, 37) |
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495 z = linspace(0, 100, 11) |
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496 \end{lstlisting} |
|
497 \pause |
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498 \begin{lstlisting} |
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499 x, y, z = mgrid[0:360:37j,-89:89:37j, |
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500 0:100:11j] |
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501 t = 288.15 - 6.5*z |
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502 mlab.contour3d(x, y, z, t) |
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503 mlab.outline() |
|
504 mlab.colorbar() |
|
505 \end{lstlisting} |
|
506 \end{frame} |
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507 |
|
508 \begin{frame}[fragile] |
|
509 \frametitle{Exercise: Lorenz equation} |
|
510 \begin{columns} |
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511 \column{0.25\textwidth} |
|
512 \begin{eqnarray*} |
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513 \frac{d x}{dt} &=& s (y-x)\\ |
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514 \frac{d y}{d t} &=& rx -y -xz\\ |
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515 \frac{d z}{d t} &=& xy - bz\\ |
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516 \end{eqnarray*} |
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517 \column{0.25\textwidth} |
|
518 Let $s=10,$ |
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519 $r=28,$ |
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520 $b=8./3.$ |
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521 \end{columns} |
|
522 \structure{\Large Region of interest} |
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523 \begin{lstlisting} |
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524 x, y, z = mgrid[-50:50:20j,-50:50:20j, |
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525 -10:60:20j] |
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526 \end{lstlisting} |
|
527 \inctime{20} |
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528 |
|
529 \end{frame} |
|
530 \begin{frame}[fragile] |
|
531 \frametitle{Solution} |
|
532 \begin{lstlisting} |
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533 def lorenz(x,y,z,s=10.,r=28.,b=8./3.): |
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534 u = s*(y-x) |
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535 v = r*x-y-x*z |
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536 w = x*y-b*z |
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537 return u,v,w |
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538 x,y,z = mgrid [-50:50:20j,-50:50:20j, |
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539 -10:60:20j ] |
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540 u,v,w = lorenz( x , y , z ) |
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541 # Your plot here |
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542 # |
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543 mlab.show() |
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544 |
|
545 \end{lstlisting} |
|
546 \end{frame} |
|
547 |
|
548 \begin{frame} |
|
549 \frametitle{We have covered:} |
158 \begin{itemize} |
550 \begin{itemize} |
159 \item python gcd.py |
551 \item Need of visualization. |
|
552 \item Using mlab to create 3 D plots. |
|
553 \item Mayavi Toolkit. |
160 \end{itemize} |
554 \end{itemize} |
161 \end{frame} |
555 \end{frame} |
162 |
556 |
163 \begin{frame}[fragile] |
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164 \frametitle{Find lcm using our gcd module} |
|
165 \begin{itemize} |
|
166 \item Open lcm.py |
|
167 \item $lcm = \frac{a*b}{gcd(a,b)}$ |
|
168 \end{itemize} |
|
169 \begin{lstlisting} |
|
170 from gcd import gcd |
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171 def lcm(a, b): |
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172 return (a * b) / gcd(a, b) |
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173 |
|
174 print lcm(14, 56) |
|
175 \end{lstlisting} |
|
176 \begin{itemize} |
|
177 \item python lcm.py |
|
178 \end{itemize} |
|
179 \begin{lstlisting} |
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180 5 |
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181 4 |
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182 56 |
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183 \end{lstlisting} |
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184 \end{frame} |
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185 |
|
186 \begin{frame}[fragile] |
|
187 \frametitle{Writing stand-alone module} |
|
188 Edit gcd.py file to: |
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189 \begin{lstlisting} |
|
190 def gcd(a, b): |
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191 if a % b == 0: |
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192 return b |
|
193 return gcd(b, a%b) |
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194 |
|
195 if __name__ == "__main__": |
|
196 print gcd(15, 65) |
|
197 print gcd(16, 76) |
|
198 \end{lstlisting} |
|
199 \begin{itemize} |
|
200 \item python gcd.py |
|
201 \item python lcm.py |
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202 \end{itemize} |
|
203 \end{frame} |
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204 |
|
205 \begin{frame}[fragile] |
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206 \frametitle{More use of main} |
|
207 For automating tests. |
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208 \begin{lstlisting} |
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209 if __name__ == '__main__': |
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210 for line in open('numbers.txt'): |
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211 numbers = line.split() |
|
212 x = int(numbers[0]) |
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213 y = int(numbers[1]) |
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214 result = (int(numbers[2])) |
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215 assert gcd(x, y) == result |
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216 \end{lstlisting} |
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217 \end{frame} |
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218 |
|
219 \section{Coding Style} |
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220 \begin{frame}{Readability and Consistency} |
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221 \begin{itemize} |
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222 \item Readability Counts!\\Code is read more often than its written. |
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223 \item Consistency! |
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224 \item Know when to be inconsistent. |
|
225 \end{itemize} |
|
226 \end{frame} |
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227 |
|
228 \begin{frame}[fragile] \frametitle{A question of good style} |
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229 \begin{lstlisting} |
|
230 amount = 12.68 |
|
231 denom = 0.05 |
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232 nCoins = round(amount/denom) |
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233 rAmount = nCoins * denom |
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234 \end{lstlisting} |
|
235 \pause |
|
236 \begin{block}{Style Rule \#1} |
|
237 Naming is 80\% of programming |
|
238 \end{block} |
|
239 \end{frame} |
|
240 |
|
241 \begin{frame}[fragile] |
|
242 \frametitle{Code Layout} |
|
243 \begin{itemize} |
|
244 \item Indentation |
|
245 \item Tabs or Spaces?? |
|
246 \item Maximum Line Length |
|
247 \item Blank Lines |
|
248 \item Encodings |
|
249 \end{itemize} |
|
250 \end{frame} |
|
251 |
|
252 \begin{frame}{Whitespaces in Expressions} |
|
253 \begin{itemize} |
|
254 \item When to use extraneous whitespaces?? |
|
255 \item When to avoid extra whitespaces?? |
|
256 \item Use one statement per line |
|
257 \end{itemize} |
|
258 \end{frame} |
|
259 |
|
260 \begin{frame}{Comments} |
|
261 \begin{itemize} |
|
262 \item No comments better than contradicting comments |
|
263 \item Block comments |
|
264 \item Inline comments |
|
265 \end{itemize} |
|
266 \end{frame} |
|
267 |
|
268 \begin{frame}{Docstrings} |
|
269 \begin{itemize} |
|
270 \item When to write docstrings? |
|
271 \item Ending the docstrings |
|
272 \item One liner docstrings |
|
273 \end{itemize} |
|
274 More information at PEP8: http://www.python.org/dev/peps/pep-0008/ |
|
275 \inctime{5} |
|
276 \end{frame} |
|
277 |
|
278 \section{Debugging} |
|
279 \subsection{Errors and Exceptions} |
|
280 \begin{frame}[fragile] |
|
281 \frametitle{Errors} |
|
282 \begin{lstlisting} |
|
283 In []: while True print 'Hello world' |
|
284 \end{lstlisting} |
|
285 \pause |
|
286 \begin{lstlisting} |
|
287 File "<stdin>", line 1, in ? |
|
288 while True print 'Hello world' |
|
289 ^ |
|
290 SyntaxError: invalid syntax |
|
291 \end{lstlisting} |
|
292 \end{frame} |
|
293 |
|
294 \begin{frame}[fragile] |
|
295 \frametitle{Exceptions} |
|
296 \begin{lstlisting} |
|
297 In []: print spam |
|
298 \end{lstlisting} |
|
299 \pause |
|
300 \begin{lstlisting} |
|
301 Traceback (most recent call last): |
|
302 File "<stdin>", line 1, in <module> |
|
303 NameError: name 'spam' is not defined |
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304 \end{lstlisting} |
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305 \end{frame} |
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306 |
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307 \begin{frame}[fragile] |
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308 \frametitle{Exceptions} |
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309 \begin{lstlisting} |
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310 In []: 1 / 0 |
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311 \end{lstlisting} |
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312 \pause |
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313 \begin{lstlisting} |
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314 Traceback (most recent call last): |
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315 File "<stdin>", line 1, in <module> |
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316 ZeroDivisionError: integer division |
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317 or modulo by zero |
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318 \end{lstlisting} |
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319 \end{frame} |
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320 |
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321 \begin{frame}[fragile] |
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322 \frametitle{Handling Exceptions} |
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323 Python uses \typ{try} and \typ{except} clause. |
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324 %%Revisiting the raw\_input |
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325 \begin{lstlisting} |
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326 a = raw_input('Enter number(Q to quit):') |
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327 try: |
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328 num = int(a) |
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329 print num |
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330 except: |
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331 if a == 'Q': |
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332 print 'Exiting...' |
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333 else: |
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334 print 'Wrong input!' |
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335 \end{lstlisting} |
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336 |
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337 |
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338 \end{frame} |
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339 |
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340 %% \begin{frame}[fragile] |
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341 %% \frametitle{Solving it with \typ{try} and \typ{except}} |
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342 %% \vspace{-0.2in} |
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343 %% \begin{lstlisting} |
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344 %% highest = 0 |
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345 %% for record in open('sslc1.txt'): |
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346 %% fields = record.split(';') |
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347 %% try: |
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348 %% total = 0 |
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349 %% for score_str in fields[3:8]: |
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350 %% score = int(score_str) |
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351 %% total += score |
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352 %% if total > highest: |
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353 %% highest = total |
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354 %% except: |
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355 %% pass |
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356 %% print highest |
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357 %% \end{lstlisting} |
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358 %% \end{frame} |
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359 \subsection{Strategy} |
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360 \begin{frame}[fragile] |
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361 \frametitle{Debugging effectively} |
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362 \begin{itemize} |
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363 \item \typ{print} based strategy |
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364 \item Process: |
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365 \end{itemize} |
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366 \begin{center} |
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367 \pgfimage[interpolate=true,width=5cm,height=5cm]{DebugginDiagram.png} |
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368 \end{center} |
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369 \end{frame} |
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370 |
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371 \begin{frame}[fragile] |
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372 \frametitle{Debugging effectively} |
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373 \begin{itemize} |
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374 \item Using \typ{\%debug} in IPython |
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375 \end{itemize} |
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376 \end{frame} |
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377 |
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378 \begin{frame}[fragile] |
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379 \frametitle{Debugging in IPython} |
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380 \small |
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381 \begin{lstlisting} |
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382 In []: import mymodule |
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383 In []: mymodule.test() |
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384 --------------------------------------------- |
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385 NameError Traceback (most recent call last) |
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386 <ipython console> in <module>() |
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387 mymodule.py in test() |
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388 1 def test(): |
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389 ----> 2 print spam |
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390 NameError: global name 'spam' is not defined |
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391 |
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392 In []: %debug |
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393 > mymodule.py(2)test() |
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394 0 print spam |
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395 ipdb> |
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396 \end{lstlisting} |
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397 \inctime{15} |
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398 \end{frame} |
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399 |
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400 \subsection{Exercise} |
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401 \begin{frame}[fragile] |
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402 \frametitle{Debugging: Exercise} |
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403 \small |
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404 \begin{lstlisting} |
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405 science = {} |
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406 |
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407 for record in open('sslc1.txt'): |
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408 fields = record.split(';') |
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409 region_code = fields[0].strip() |
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410 |
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411 score_str = fields[6].strip() |
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412 score = int(score_str) if score_str != 'AA' |
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413 else 0 |
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414 |
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415 if score > 90: |
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416 science[region_code] += 1 |
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417 |
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418 pie(science.values(), labels=science.keys()) |
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419 savefig('science.png') |
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420 \end{lstlisting} |
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421 \inctime{10} |
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422 \end{frame} |
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423 |
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424 %% \begin{frame} |
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425 %% \frametitle{Testing} |
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426 |
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427 %% \begin{itemize} |
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428 %% \item Writing tests is really simple! |
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429 |
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430 %% \item Using nose. |
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431 |
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432 %% \item Example! |
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433 %% \end{itemize} |
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434 %% \end{frame} |
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435 |
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436 \section{Test Driven Approach} |
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437 \begin{frame} |
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438 \frametitle{Need for Testing!} |
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439 |
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440 \begin{itemize} |
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441 \item Quality |
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442 \item Regression |
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443 \item Documentation |
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444 \end{itemize} |
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445 %% \vspace*{0.25in} |
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446 %% \emphbar{It is to assure that section of code is working as it is supposed to work} |
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447 \end{frame} |
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448 |
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449 \begin{frame}[fragile] |
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450 \frametitle{Example} |
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451 \begin{block}{Problem Statement} |
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452 Write a function to check whether a given input |
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453 string is a palindrome. |
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454 \end{block} |
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455 \end{frame} |
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456 |
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457 \begin{frame}[fragile] |
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458 \frametitle{Function: palindrome.py} |
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459 \begin{lstlisting} |
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460 def is_palindrome(input_str): |
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461 return input_str == input_str[::-1] |
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462 \end{lstlisting} |
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463 \end{frame} |
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464 |
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465 \begin{frame}[fragile] |
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466 \frametitle{Test for the palindrome: palindrome.py} |
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467 \begin{lstlisting} |
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468 def test_function_normal_words(): |
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469 input = "noon" |
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470 assert is_palindrome(input) == True |
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471 |
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472 if __name__ == "main'': |
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473 test_function_normal_words() |
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474 \end{lstlisting} |
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475 \end{frame} |
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476 |
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477 \begin{frame}[fragile] |
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478 \frametitle{Running the tests.} |
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479 \begin{lstlisting} |
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480 $ nosetests palindrome.py |
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481 . |
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482 ---------------------------------------------- |
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483 Ran 1 test in 0.001s |
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484 |
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485 OK |
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486 \end{lstlisting} |
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487 \end{frame} |
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488 |
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489 \begin{frame}[fragile] |
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490 \frametitle{Exercise: Including new tests.} |
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491 \begin{lstlisting} |
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492 def test_function_ignore_cases_words(): |
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493 input = "Noon" |
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494 assert is_palindrome(input) == True |
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495 \end{lstlisting} |
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496 \vspace*{0.25in} |
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497 Check\\ |
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498 \PythonCode{$ nosetests palindrome.py} \\ |
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499 \begin{block}{Task} |
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500 Tweak the code to pass this test. |
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501 \end{block} |
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502 \end{frame} |
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503 |
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504 %\begin{frame}[fragile] |
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505 % \frametitle{Lets write some test!} |
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506 %\begin{lstlisting} |
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507 %#for form of equation y=mx+c |
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508 %#given m and c for two equation, |
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509 %#finding the intersection point. |
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510 %def intersect(m1,c1,m2,c2): |
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511 % x = (c2-c1)/(m1-m2) |
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512 % y = m1*x+c1 |
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513 % return (x,y) |
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514 %\end{lstlisting} |
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515 % |
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516 %Create a simple test for this |
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517 % |
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518 %function which will make it fail. |
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519 % |
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520 %\inctime{15} |
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521 %\end{frame} |
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522 % |
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523 |
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524 %% \begin{frame}[fragile] |
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525 %% \frametitle{Exercise} |
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526 %% Based on Euclid's algorithm: |
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527 %% \begin{center} |
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528 %% $gcd(a,b)=gcd(b,b\%a)$ |
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529 %% \end{center} |
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530 %% gcd function can be written as: |
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531 %% \begin{lstlisting} |
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532 %% def gcd(a, b): |
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533 %% if a%b == 0: return b |
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534 %% return gcd(b, a%b) |
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535 %% \end{lstlisting} |
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536 %% \vspace*{-0.15in} |
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537 %% \begin{block}{Task} |
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538 %% \begin{itemize} |
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539 %% \item Write at least |
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540 %% two tests for above mentioned function. |
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541 %% \item Write a non recursive implementation |
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542 %% of gcd(), and test it using already |
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543 %% written tests. |
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544 %% \end{itemize} |
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545 %% \end{block} |
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546 |
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547 %% \inctime{15} |
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548 %% \end{frame} |
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549 |
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550 \begin{frame} |
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551 \frametitle{Summary} |
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552 We have coverd: |
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553 \begin{itemize} |
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554 \item Following and Resolving Error Messages. |
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555 \item Exceptions. |
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556 \item Handling exceptions |
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557 \item Approach for Debugging. |
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558 \item Writting and running tests. |
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559 \end{itemize} |
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560 \end{frame} |
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561 |
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562 \end{document} |
557 \end{document} |
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558 |