Reviewed Basic datatypes LO.
Objective Questions
-------------------
1. How do you retrieve the recent 5 commands
a. ``%hist``
#. ``%hist -5``
#. ``%hist 5``
#. ``%hist 5-10``
Answer: ``%hist 5``
2. If there were 20 commands typed and ``%hist`` is used. How many commands
will be displayed.
a. 10
#. 20
#. 21
#. 19
Answer: 21
3. is ``%hist`` considered as a command
a. True
#. False
Answer: True
4. how do you retreive the commands from 20 to 50 (inclusive of 20 and 50)
a. ``%hist 20 50``
#. ``%hist 19 50``
#. ``%hist 19 51``
#. ``%hist 21 50``
Answer: ``%hist 20 50``
5. What does the ``%hist 2 5 7`` command do
a. lists the second, fifth and seventh commands
#. lists the commands from 2 to 5 and the seventh command
#. raises an error
#. lists the commands 2 to 7
Answer: raises an error
6. How many commands are displayed when lot of coomands were typed and
``%hist`` is used.
a. 20
#. 10
#. 50
#. 40
Answer: 40
7. How do you save the lines 2 3 4 5 7 9 10 11
a. ``%save filepath 2-5 7 9-11``
#. ``%save filepath 2-11``
#. ``%save filepath``
#. ``%save 2-5 7 9 10 11``
Answer: ``%save filepath 2-5 7 9-11``
8. You are working in /home/user. Where is the file saved when you do
``%save hello.py 1-3``
a. /home/user/hello.py
#. /hello.py
#. /home/hello.py
#. /home/user/ipython/hello.py
Answer: /home/user/hello.py
9. Which lines are saved by the command ``%save filepath 2-5 7 1`` and in
which order
a. 2 3 4 5 7 1
#. 1 2 3 4 5 6 7
#. 2 5 7 1
#. 1 2 5 7
10. What happens when ``%save filepath line_numbers`` is used and a file
already exists in that path.
a. It is overwritten
#. The commands are added to the file
#. It raises an error
#. A prompt to confirm overwriting is displayed
Answer: A prompt to confirm overwriting is displayed
11. Read through the documentation of ``%hist`` and find its alternative name
Answer: ``%history``
12. Are ``%run /home/user/saved.py`` and ``%run /home/user/saved`` the same
a. Yes
#. No
Answer: Yes
13. The file hello.py contains only one command ``x = x + 1``. What happens
when you do ``%run hello.py``
Answer: Raises a nameerror
14. The file hello.py contains only one command ``x = x + 1``. If value of x
is 5 and what does ``%run -i hello.py`` do.
a. raises an error
#. increments value of x by 1
#. Does nothing
Answer: increments the value of x by 1