Difference between revisions of "Python/C2/Getting-started-with-ipython/English-timed"
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(Created page with '{| border=1 !Timing !Narration |- | 0:00 | Hello Friends and Welcome to the tutorial on "getting started with <tt>ipython</tt>". |- | 0:06 | At the end of this tutorial, you wi…') |
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| 0:00 | | 0:00 | ||
− | | Hello Friends and Welcome to the tutorial on "getting started with | + | | Hello Friends and Welcome to the tutorial on "getting started with ipython". |
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− | | 0: | + | | 0:07 |
| At the end of this tutorial, you will be able to, | | At the end of this tutorial, you will be able to, | ||
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− | | 0: | + | | 0:27 |
| IPython is an enhanced Python interpreter that provides features like tab-completion, easier access to help and many other functionalities. | | IPython is an enhanced Python interpreter that provides features like tab-completion, easier access to help and many other functionalities. | ||
− | |||
|- | |- | ||
− | | 0: | + | | 0:37 |
− | |Let us first see how to start the | + | |Let us first see how to start the ipython interpreter. |
|- | |- | ||
− | | 0: | + | | 0:41 |
− | | First open the terminal, type | + | | First open the terminal, type ipython in the terminal and hit enter. |
|- | |- | ||
− | | 0: | + | | 0:51 |
− | | | + | | After getting some information about the version of Python installed and some help commands, we get a prompt with In[1]:. |
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− | | 1: | + | | 1:09 |
| Now, lets see how we can quit the ipython interpreter, press Ctrl-D. | | Now, lets see how we can quit the ipython interpreter, press Ctrl-D. | ||
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|- | |- | ||
− | | 1: | + | | 1:28 |
| Press y. | | Press y. | ||
|- | |- | ||
− | | 1: | + | | 1:32 |
− | | Now since we have quit the interpretor, let us start it again by typing | + | | Now since we have quit the interpretor, let us start it again by typing ipython |
|- | |- | ||
− | | 1: | + | | 1:42 |
| And now let's see, how to use the interpreter. | | And now let's see, how to use the interpreter. | ||
|- | |- | ||
− | | 1: | + | | 1:46 |
|Start with the simplest thing, addition. | |Start with the simplest thing, addition. | ||
|- | |- | ||
| 1:48 | | 1:48 | ||
− | |type 1+2 at the prompt. | + | |type ''1+2 ''at the prompt. |
|- | |- | ||
− | | 1: | + | | 1:55 |
− | |IPython promptly gives back the output as 3. | + | |IPython promptly gives back the output as ''3''. |
|- | |- | ||
− | | 1: | + | | 1:59 |
− | |Notice that the output is displayed with an | + | |Notice that the output is displayed with an Out[1] indication. |
|- | |- | ||
| 2:05 | | 2:05 | ||
− | | Now, Let us now try few more operations such as, 5 minus 3, 7 minus 4, 6 into 5. | + | | Now, Let us now try few more operations such as, ''5 minus 3, 7 minus 4, 6 into 5''. |
|- | |- | ||
− | | 2: | + | | 2:23 |
| Now let's see how the ipython remembers the history of commands. | | Now let's see how the ipython remembers the history of commands. | ||
|- | |- | ||
− | | 2: | + | | 2:29 |
− | |For example | + | |For example ,''print 1+2''. |
|- | |- | ||
− | | 2: | + | | 2:33 |
− | |Instead of typing the whole thing,use the up arrow key to go back to the command | + | |Instead of typing the whole thing,use the up arrow key to go back to the command ''1+2''which we did before, now use the left-arrow key to navigate to the beginning of the line and type the word``print``and press space. |
|- | |- | ||
− | | 2: | + | | 2:55 |
| We have changed the line to print 1+2, now press enter. | | We have changed the line to print 1+2, now press enter. | ||
|- | |- | ||
− | | 3: | + | | 3:02 |
− | |The interpreter prints the result as 3. | + | |The interpreter prints the result as ''3''. |
|- | |- | ||
− | | 3: | + | | 3:06 |
| Please note that the indication Out square brackets is not shown here. | | Please note that the indication Out square brackets is not shown here. | ||
|- | |- | ||
− | | 3: | + | | 3:11 |
− | | Now let us do print 10 into 2. | + | | Now let us do print'' 10 into 2''. |
|- | |- | ||
− | | 3: | + | | 3:16 |
− | |We use the up arrow key to navigate to the previous command 1+2. | + | |We use the up arrow key to navigate to the previous command'' 1+2''. |
|- | |- | ||
− | | 3: | + | | 3:22 |
− | | Now change | + | | Now change ''1 plus 2 to 10 into 2'' and press enter. |
|- | |- | ||
− | | 3: | + | | 3:34 |
| Till now, we saw how to invoke the ipython interpreter,quit the ipython and navigate through previous commands in ipython. | | Till now, we saw how to invoke the ipython interpreter,quit the ipython and navigate through previous commands in ipython. | ||
|- | |- | ||
− | | 3: | + | | 3:42 |
|Now, let's see, what is tab-completion?. | |Now, let's see, what is tab-completion?. | ||
|- | |- | ||
− | | 3: | + | | 3:47 |
− | |let's take an example, suppose we want to use the function | + | |let's take an example, suppose we want to use the function round. |
|- | |- | ||
− | | 3: | + | | 3:52 |
− | | For this we just type | + | | For this we just type ''ro'' at the prompt and press the tab key. |
|- | |- | ||
− | | | + | | 4.00 |
− | | As you can see on the terminal, IPython completes the command | + | | As you can see on the terminal, IPython completes the command ''ro'' into round, This feature of ipython is called the tab-completion. |
|- | |- | ||
| 4:08 | | 4:08 | ||
− | | Let's see some more possibilities of tab completion just type | + | | Let's see some more possibilities of tab completion just type'' r'' and then press the'' tab''. |
|- | |- | ||
− | | 4: | + | | 4:19 |
− | | As you can see that IPython does not complete the command. This is because, there are many possibilities of | + | | As you can see that IPython does not complete the command. This is because, there are many possibilities of ''r'' therefore it just lists out all the possible completions of r. |
|- | |- | ||
− | | 4: | + | | 4:31 |
| Now let's try out an exercise. | | Now let's try out an exercise. | ||
|- | |- | ||
− | | 4: | + | | 4:33 |
| Pause the video,solve the problem and resume the video. | | Pause the video,solve the problem and resume the video. | ||
|- | |- | ||
− | | 4: | + | | 4:39 |
| 1. find out the commands starting with "ab"? | | 1. find out the commands starting with "ab"? | ||
|- | |- | ||
− | | 4: | + | | 4:44 |
| 2. list out the commands starting with "a"? | | 2. list out the commands starting with "a"? | ||
|- | |- | ||
− | | 4: | + | | 4:54 |
− | | | + | |'' ab'' tab completes to''abs'' and ''a<tab></tt> gives us a list of all the commands starting with a. |
|- | |- | ||
− | | 5: | + | | 5:07 |
| Now, let's see what the functions abs is used for. | | Now, let's see what the functions abs is used for. | ||
|- | |- | ||
− | | 5: | + | | 5:12 |
| We will use the help features of ipython to find out this. | | We will use the help features of ipython to find out this. | ||
|- | |- | ||
| 5:15 | | 5:15 | ||
− | | To see the documentation of a function, type the function name followed by a | + | | To see the documentation of a function, type the function name followed by a question mark and hit enter. |
|- | |- | ||
− | | 5: | + | | 5:24 |
| Ipython interpreter will show the documentation for the function. | | Ipython interpreter will show the documentation for the function. | ||
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|- | |- | ||
− | | 5: | + | | 5:38 |
− | | As the documentation says, | + | | As the documentation says, ''abs'' accepts a number as an input and returns it's absolute value. |
|- | |- | ||
− | | 5: | + | | 5:46 |
|lets see few examples, | |lets see few examples, | ||
|- | |- | ||
− | | 5: | + | | 5:49 |
− | |Type abs(-19) and abs(19) on the interpreter. | + | |Type ''abs(-19)'' and'' abs(19)'' on the interpreter. |
|- | |- | ||
− | | 6: | + | | 6:04 |
− | |We get 19, as expected, in both the cases. | + | |We get ''19'', as expected, in both the cases. |
|- | |- | ||
− | | 6: | + | | 6:08 |
− | | Now lets try it for decimal numbers; lets try abs(-10.5), we got 10.5 as the result. | + | | Now lets try it for decimal numbers; lets try'' abs(-10.5)'', we got ''10.5'' as the result. |
|- | |- | ||
− | | 6: | + | | 6:24 |
| Pause the video here, try out the following exercise and resume the video. | | Pause the video here, try out the following exercise and resume the video. | ||
|- | |- | ||
− | | 6: | + | | 6:31 |
− | |Look-up the documentation of | + | |Look-up the documentation of ''round'' and see how to use it. |
|- | |- | ||
− | | 6: | + | | 6:39 |
− | | And you can look up the documentation of the function round by typing round | + | | And you can look up the documentation of the function round by typing round ''question mark'' in the ipython interpreter. |
|- | |- | ||
| 6:47 | | 6:47 | ||
− | | If you notice, there are extra square brackets around | + | | If you notice, there are extra square brackets around ''ndigits''. |
|- | |- | ||
− | | 6: | + | | 6:53 |
− | | This means that | + | | This means that ''ndigits'' is optional and 0 is the default value. |
|- | |- | ||
− | | 6: | + | | 6:58 |
| Optional parameters are shown in square brackets in Python documentation. | | Optional parameters are shown in square brackets in Python documentation. | ||
|- | |- | ||
− | | 7: | + | | 7:03 |
− | | | + | |A function ''round'', rounds a number to a given precision. |
|- | |- | ||
− | | 7: | + | | 7:09 |
| Pause the video here, try out the following exercise and resume the video. | | Pause the video here, try out the following exercise and resume the video. | ||
|- | |- | ||
− | | 7: | + | | 7:16 |
− | | | + | | let us now try few more examples with the function round. |
|- | |- | ||
− | | 7: | + | | 7:21 |
− | | Check the output of round(2.48) round(2.48, 1) round(2.48, 2) round(2.484) round(2.484, 1) round(2.484, 2) | + | | Check the output of ''round(2.48) round(2.48, 1) round(2.48, 2) round(2.484) round(2.484, 1) round(2.484, 2)'' |
|- | |- | ||
− | | 7: | + | | 7:43 |
− | | Now, we | + | | Now, we got'' 2.0, 2.5 and 2.48'', which are what we expect. |
|- | |- | ||
| 7:54 | | 7:54 | ||
− | | Let's now see how to correct typing errors which we often make while typing at the terminal. | + | | Let's now see how to correct typing errors, which we often make while typing at the terminal. |
|- | |- | ||
− | | | + | | 08.01 |
| As already shown, if we haven't hit the enter key already, we could navigate using the arrow keys and make deletions using delete or backspace key and correct the errors. | | As already shown, if we haven't hit the enter key already, we could navigate using the arrow keys and make deletions using delete or backspace key and correct the errors. | ||
|- | |- | ||
− | | 8: | + | | 8:12 |
|let us make a typing error deliberately, type round(2.484 and hit enter, without closing the parenthesis. | |let us make a typing error deliberately, type round(2.484 and hit enter, without closing the parenthesis. | ||
|- | |- | ||
− | | 8: | + | | 8:25 |
− | | We get a prompt with dots. | + | | We get a prompt with ''dots'' . |
|- | |- | ||
− | | 8: | + | | 8:28 |
− | |This prompt is the continuation prompt of | + | |This prompt is the continuation prompt of ''ipython''. |
|- | |- | ||
− | | 8: | + | | 8:32 |
| It appears when, the previous line is incomplete. | | It appears when, the previous line is incomplete. | ||
|- | |- | ||
− | | 8: | + | | 8:36 |
| now complete the command of the same examples with close parenthesis and press enter. | | now complete the command of the same examples with close parenthesis and press enter. | ||
|- | |- | ||
− | |8: | + | |8:49 |
− | |We got the expected output that is 2.0 | + | |We got the expected output that is ''2.0'' |
|- | |- | ||
| 8:51 | | 8:51 | ||
− | | In other instances, if we commit a typing error with a longer and more complex expression and end up with the continuation prompt, we can type Ctrl-C to interrupt the command and | + | | In other instances, if we commit a typing error with a longer and more complex expression and end up with the continuation prompt, we can type Ctrl-C to interrupt the command and get back to the <tt>ipython</tt> input prompt. |
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|- | |- | ||
| 9:22 | | 9:22 | ||
− | | 1. type round(2.484, and press enter. and then cancel the command using Ctrl-C. | + | | 1.type round(2.484, and press enter. and then cancel the command using ''Ctrl-C''. |
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|- | |- | ||
− | | 10: | + | | 10:09 |
− | | Now, let us revise quickly what we learnt today. In this tutorial, | + | | Now, let us revise quickly what we learnt today. In this tutorial,welearnt to, |
|- | |- | ||
| 10:15 | | 10:15 | ||
− | | 1. Invoke the | + | | 1. Invoke the ipython interpreter by typing ipython. |
|- | |- | ||
− | | 10: | + | | 10:20 |
− | | 2. To quit the | + | | 2. To quit the ipython interpreter by using <ctrl>d.</nowiki> |
|- | |- | ||
| 10:22 | | 10:22 | ||
− | | 3. To navigate in the history of | + | | 3. To navigate in the history of ipython by using the arrow keys. |
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− | | 10: | + | | 10:30 |
− | | 5. To see the documentation of functions using | + | | 5. To see the documentation of functions using question mark. |
|- | |- | ||
− | | 10: | + | | 10:34 |
− | | 6. To | + | | 6. To Interrupt using <ctrl>c when we make an error. |
|- | |- | ||
− | | 10: | + | | 10:39 |
| Here are some self assessment questions for you to solve | | Here are some self assessment questions for you to solve | ||
|- | |- | ||
− | | 10: | + | | 10:44 |
− | | | + | | '''ipython is a programming language similar to Python. |
|- | |- | ||
| 10:50 | | 10:50 | ||
− | |''' | + | |''' True or False'' |
|- | |- | ||
− | | 10: | + | | 10:53 |
− | | Second one. Which key combination quits <tt>ipython</tt>? | + | | Second one. Which key combination quits <tt>ipython</tt>? '' Ctrl + C Ctrl + D Alt + C Alt + D'' |
|- | |- | ||
− | | 11: | + | | 11:03 |
− | | The last one. Which character is used at the end of a command, in Ipython to display the documentation. under score (_) | + | | And The last one. Which character is used at the end of a command, in Ipython to display the documentation. under score'' (_) ''question mark'' (?)'' exclamation mark'' (!)'' ampersand ''(&)'' |
|- | |- | ||
− | | 11: | + | | 11:16 |
| And the answers are, | | And the answers are, | ||
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− | | 11: | + | | 11:23 |
− | | Second one is We use Ctrl D to quit Ipython interpreter. | + | | Second one is We use ''Ctrl D'' to quit Ipython interpreter. |
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Line 361: | Line 360: | ||
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− | | 11: | + | | 11:36 |
| So we hope you have enjoyed this tutorial and found it useful. | | So we hope you have enjoyed this tutorial and found it useful. | ||
Revision as of 15:23, 1 March 2013
Timing | Narration |
---|---|
0:00 | Hello Friends and Welcome to the tutorial on "getting started with ipython". |
0:07 | At the end of this tutorial, you will be able to,
|
0:27 | IPython is an enhanced Python interpreter that provides features like tab-completion, easier access to help and many other functionalities. |
0:37 | Let us first see how to start the ipython interpreter. |
0:41 | First open the terminal, type ipython in the terminal and hit enter. |
0:51 | After getting some information about the version of Python installed and some help commands, we get a prompt with In[1]:. |
0:59 | But, if you get an error saying 'ipython is not installed' then refer to the tutorial on how to install the packages. |
1:09 | Now, lets see how we can quit the ipython interpreter, press Ctrl-D. |
1:17 | A prompt will appear to confirm whether you really want to exit, type y to say yes and quit ipython and n to say no if you don't want to quit the ipython. |
1:28 | Press y. |
1:32 | Now since we have quit the interpretor, let us start it again by typing ipython |
1:42 | And now let's see, how to use the interpreter. |
1:46 | Start with the simplest thing, addition. |
1:48 | type 1+2 at the prompt. |
1:55 | IPython promptly gives back the output as 3. |
1:59 | Notice that the output is displayed with an Out[1] indication. |
2:05 | Now, Let us now try few more operations such as, 5 minus 3, 7 minus 4, 6 into 5. |
2:23 | Now let's see how the ipython remembers the history of commands. |
2:29 | For example ,print 1+2. |
2:33 | Instead of typing the whole thing,use the up arrow key to go back to the command 1+2which we did before, now use the left-arrow key to navigate to the beginning of the line and type the word``print``and press space. |
2:55 | We have changed the line to print 1+2, now press enter. |
3:02 | The interpreter prints the result as 3. |
3:06 | Please note that the indication Out square brackets is not shown here. |
3:11 | Now let us do print 10 into 2. |
3:16 | We use the up arrow key to navigate to the previous command 1+2. |
3:22 | Now change 1 plus 2 to 10 into 2 and press enter. |
3:34 | Till now, we saw how to invoke the ipython interpreter,quit the ipython and navigate through previous commands in ipython. |
3:42 | Now, let's see, what is tab-completion?. |
3:47 | let's take an example, suppose we want to use the function round. |
3:52 | For this we just type ro at the prompt and press the tab key. |
4.00 | As you can see on the terminal, IPython completes the command ro into round, This feature of ipython is called the tab-completion. |
4:08 | Let's see some more possibilities of tab completion just type r and then press the tab. |
4:19 | As you can see that IPython does not complete the command. This is because, there are many possibilities of r therefore it just lists out all the possible completions of r. |
4:31 | Now let's try out an exercise. |
4:33 | Pause the video,solve the problem and resume the video. |
4:39 | 1. find out the commands starting with "ab"? |
4:44 | 2. list out the commands starting with "a"? |
4:54 | ab tab completes toabs and a<tab></tt> gives us a list of all the commands starting with a. |
5:07 | Now, let's see what the functions abs is used for. |
5:12 | We will use the help features of ipython to find out this. |
5:15 | To see the documentation of a function, type the function name followed by a question mark and hit enter. |
5:24 | Ipython interpreter will show the documentation for the function. |
5:27 | Let us see the documentation of the function abs, type abs? and press enter |
5:38 | As the documentation says, abs accepts a number as an input and returns it's absolute value. |
5:46 | lets see few examples, |
5:49 | Type abs(-19) and abs(19) on the interpreter. |
6:04 | We get 19, as expected, in both the cases. |
6:08 | Now lets try it for decimal numbers; lets try abs(-10.5), we got 10.5 as the result. |
6:24 | Pause the video here, try out the following exercise and resume the video. |
6:31 | Look-up the documentation of round and see how to use it. |
6:39 | And you can look up the documentation of the function round by typing round question mark in the ipython interpreter. |
6:47 | If you notice, there are extra square brackets around ndigits. |
6:53 | This means that ndigits is optional and 0 is the default value. |
6:58 | Optional parameters are shown in square brackets in Python documentation. |
7:03 | A function round, rounds a number to a given precision. |
7:09 | Pause the video here, try out the following exercise and resume the video. |
7:16 | let us now try few more examples with the function round. |
7:21 | Check the output of round(2.48) round(2.48, 1) round(2.48, 2) round(2.484) round(2.484, 1) round(2.484, 2) |
7:43 | Now, we got 2.0, 2.5 and 2.48, which are what we expect. |
7:54 | Let's now see how to correct typing errors, which we often make while typing at the terminal. |
08.01 | As already shown, if we haven't hit the enter key already, we could navigate using the arrow keys and make deletions using delete or backspace key and correct the errors. |
8:12 | let us make a typing error deliberately, type round(2.484 and hit enter, without closing the parenthesis. |
8:25 | We get a prompt with dots . |
8:28 | This prompt is the continuation prompt of ipython. |
8:32 | It appears when, the previous line is incomplete. |
8:36 | now complete the command of the same examples with close parenthesis and press enter. |
8:49 | We got the expected output that is 2.0 |
8:51 | In other instances, if we commit a typing error with a longer and more complex expression and end up with the continuation prompt, we can type Ctrl-C to interrupt the command and get back to the ipython input prompt. |
9:15 | Pause the video here, try out the following exercise and resume the video. |
9:22 | 1.type round(2.484, and press enter. and then cancel the command using Ctrl-C. |
9:45 | 2. type the command, round(2.484, 2) |
10:09 | Now, let us revise quickly what we learnt today. In this tutorial,welearnt to, |
10:15 | 1. Invoke the ipython interpreter by typing ipython. |
10:20 | 2. To quit the ipython interpreter by using <ctrl>d.</nowiki> |
10:22 | 3. To navigate in the history of ipython by using the arrow keys. |
10:28 | 4. What is tab-completion |
10:30 | 5. To see the documentation of functions using question mark. |
10:34 | 6. To Interrupt using <ctrl>c when we make an error. |
10:39 | Here are some self assessment questions for you to solve |
10:44 | ipython is a programming language similar to Python. |
10:50 | ' True or False |
10:53 | Second one. Which key combination quits ipython? Ctrl + C Ctrl + D Alt + C Alt + D |
11:03 | And The last one. Which character is used at the end of a command, in Ipython to display the documentation. under score (_) question mark (?) exclamation mark (!) ampersand (&) |
11:16 | And the answers are, |
11:18 | Ipython is not a programming language, it is just an interpreter. |
11:23 | Second one is We use Ctrl D to quit Ipython interpreter. |
11:27 | The final one is We use ? at the end of the function name to display its documentation. |
11:36 | So we hope you have enjoyed this tutorial and found it useful. |
11:39 | Thank you! |