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1 .. Objectives |
2 Script |
2 .. ---------- |
3 ======== |
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4 |
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5 Welcome to this tutorial on loading data from files. |
4 .. At the end of this tutorial, you will be able to |
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5 |
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6 .. + Read data from files, containing a single column of data using the |
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7 .. ``loadtxt`` command. |
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8 .. + Read multiple columns of data, separated by spaces or other |
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9 .. delimiters. |
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10 |
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11 |
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12 .. Prerequisites |
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13 .. ------------- |
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14 |
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15 .. 1. getting started with ``ipython`` |
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16 |
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17 .. Author : |
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18 Internal Reviewer : |
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19 External Reviewer : |
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20 Checklist OK? : <put date stamp here, if OK> [2010-10-05] |
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21 |
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22 Script |
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23 ------ |
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24 |
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25 {{{ Show the slide containing title }}} |
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26 |
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27 Hello Friends. Welcome to this tutorial on loading data from files. |
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28 |
7 {{{ Screen shows welcome slide }}} |
29 {{{ Screen shows welcome slide }}} |
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30 |
9 We often require to plot points obtained from experimental |
31 We often require to plot points obtained from experimental |
10 observations. In this tutorial we shall learn to read data from files |
32 observations. In this tutorial we shall learn to read data from files |
57 about them, later. |
79 about them, later. |
58 |
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59 Now, let us use the ``loadtxt`` command to read a file that contains |
81 Now, let us use the ``loadtxt`` command to read a file that contains |
60 two columns of data, ``pendulum.txt``. This file contains the length |
82 two columns of data, ``pendulum.txt``. This file contains the length |
61 of the pendulum in the first column and the corresponding time period |
83 of the pendulum in the first column and the corresponding time period |
62 in the second. |
84 in the second. Note that ``loadtxt`` needs both the columns to have |
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85 equal number of rows. |
63 |
86 |
64 %%1%% Pause the video here, and use the ``cat`` command to view the |
87 .. Following is an exercise that you must do. |
65 contents of this file and then resume the video. |
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66 |
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67 This is how we look at the contents of the file, ``pendulum.txt`` |
89 .. %%1%% Use the ``cat`` command to view the contents of this file. |
68 :: |
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69 |
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70 cat /home/fossee/pendulum.txt |
91 .. Please, pause the video here. Do the exercise and then continue. |
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92 |
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93 .. This is how we look at the contents of the file, ``pendulum.txt`` |
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94 .. :: |
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95 |
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96 .. cat /home/fossee/pendulum.txt |
71 |
97 |
72 .. #[Nishanth]: The first column is L values and second is T values |
98 .. #[Nishanth]: The first column is L values and second is T values |
73 from a simle pelculum experiment. |
99 from a simle pelculum experiment. |
74 Since you are using the variable names later in the |
100 Since you are using the variable names later in the |
75 script. |
101 script. |
112 |
138 |
113 {{{ show the slide with loadtxt --- other features }}} |
139 {{{ show the slide with loadtxt --- other features }}} |
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115 In this tutorial, we have learnt the basic use of the ``loadtxt`` |
141 In this tutorial, we have learnt the basic use of the ``loadtxt`` |
116 command, which is capable of doing a lot more than we have used it for |
142 command, which is capable of doing a lot more than we have used it for |
117 until now, for example |
143 until now. Let us look at an example, but before that do this |
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144 exercise. |
118 |
145 |
119 %%2%% Pause the video here, and read the file |
146 %%1%% Read the file ``pendulum_semicolon.txt`` which contains the same |
120 ``pendulum_semicolon.txt`` which contains the same data as |
147 data as ``pendulum.txt``, but the columns are separated by semi-colons |
121 ``pendulum.txt``, but the columns are separated by semi-colons instead |
148 instead of spaces. Use the IPython help to see how to do this. |
122 of spaces. Use the IPython help to see how to do this. Once you have |
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123 finished, resume the video to look at the solution. |
150 Please, pause the video here. Do the exercise and then continue. |
124 |
151 |
125 {{{ switch back to the terminal }}} |
152 {{{ switch back to the terminal }}} |
126 :: |
153 :: |
127 |
154 |
128 L, T = loadtxt('/home/fossee/pendulum_semicolon.txt', unpack=True, delimiter=';') |
155 L, T = loadtxt('/home/fossee/pendulum_semicolon.txt', unpack=True, delimiter=';') |
140 + Read data from files, containing a single column of data using the |
167 + Read data from files, containing a single column of data using the |
141 ``loadtxt`` command. |
168 ``loadtxt`` command. |
142 + Read multiple columns of data, separated by spaces or other |
169 + Read multiple columns of data, separated by spaces or other |
143 delimiters. |
170 delimiters. |
144 |
171 |
145 Thank you! |
172 {{{ Show the "sponsored by FOSSEE" slide }}} |
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173 |
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174 This tutorial was created as a part of FOSSEE project, NME ICT, MHRD India |
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175 |
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176 Hope you have enjoyed and found it useful. |
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177 Thank you! |
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178 |