Python/C3/Getting-started-with-for/English-timed - Revision history

PoojaMoolya at 05:52, 27 March 2017

2017-03-27T05:52:14Z

PoojaMoolya at 12:09, 20 February 2017

2017-02-20T12:09:51Z

Gaurav at 07:32, 10 July 2014

2014-07-10T07:32:48Z

Show changes

Sneha at 06:26, 15 March 2013

2013-03-15T06:26:05Z

Sneha at 06:15, 15 March 2013

2013-03-15T06:15:25Z

Minal: Created page with '{| border=1 !Timing !Narration |- | 0:00 | Hello and welcome to the tutorial on ''Getting started with ``for`'' loop`. |- | 0:07 | At the end of this tutorial, you will be able …'

2013-01-02T10:56:35Z

Created page with '{| border=1 !Timing !Narration |- | 0:00 | Hello and welcome to the tutorial on ''Getting started with ``for`'' loop`. |- | 0:07 | At the end of this tutorial, you will be able …'

New page

{| border=1
!Timing
!Narration
|-
| 0:00
| Hello and welcome to the tutorial on ''Getting started with ``for`'' loop`.

|-
| 0:07
| At the end of this tutorial, you will be able to,

# Write blocks of code in python using indentation.
# Use the <tt>for</tt> loop.
# Use <tt>range()</tt> function.
# Write blocks in python interpreter
# Write blocks in ipython interpreter.

|-
| 0:25
| Before beginning this tutorial,we would suggest you to complete the tutorial on "Getting started with Lists".

|-
|0:31
|In Python whitespace is significant, and the blocks are visually separated.

|-
|0:38
|The best practice is to indent the code using four spaces.

|-
|0:41
|As you can see in the slide, "Block B" is an inner block, indented by 4 spaces.

|-
|0:48
| After "Block B" the next statement in "Block A" starts from the same indentation level of other "Block A" Statements.

|-
|0:58
| Start the ipython interpreter using ipython hyphen pylab.

|-
| 1:08
| Now let us move straight into <tt>for</tt> loop.

|-
| 1:11
| Write a for loop which iterates through a list of numbers and find the square root of each number. numbers are 1369, 7225, 3364, 7056, 5625, 729, 7056, 576, 2916

|-
| 1:37
| For the problem, first we need to create a <tt>list</tt> of numbers and then iterate over the list and find the square root of each element in it.

|-
| 1:45
| And let us create a script, rather than typing it out in the interpreter itself.

|-
| 1:50
| Open your text editor and type the following code shown on the slide.

|-
| 1:56
| Now switch to your terminal and run the script .

|-
|2:05
|In the terminal run the script as percentage run space hyphen i space list underscore roots dot py.

|-
| 2:24
| So that was easy!

|-
| 2:27
| All what we did was iterate over the list element by element and then use the element for calculation.

|-
| 2:36
| Note that here we used two variables,the variable <tt>numbers</tt>, which is a list,and the other variable <tt>each</tt>, which is the element of list under consideration in each cycle of the <tt>for</tt> loop.

|-
|2:50
| The variable names can be chosen by you.

|-
| 2:52
| Note that the lines after <tt>for</tt> statement, is indented using four spaces.

|-
| 3:01
| It means that line is a part of the for loop.

|-
|3:05
|And it is a block of code, although it is only a single statement in the block.

|-
|3:10
| Also, the fourth line or the immediate line after the <tt>for</tt> block is not indented.

|-
| 3:18
| It means that it is not a part of the <tt>for</tt> loop and the lines after that dont fall in the scope of the <tt>for</tt> loop.

|-
|3:29
|Thus each block is separated by the indentation level and that marks the importance of white-spaces in Python.

|-
| 3:35
| Print the square root of numbers in the list.

|-
|3:38
| And this time let us do it right in the IPython interpreter.

|-
|3:47
| So let us create a list.

|-
| 3:53
| You will notice that, as soon as you press the enter key after for statement, the prompt changes to four dots and the cursor is not right after the four dots but there are four spaces from the dots.

|-
|4:07
|numbers is equal to within square brackets 1369, 7225, 3364, 7056, 5625, 729, 7056, 576, 2916
Then type for each in numbers colon

|-
|4:37
|So you can see the four dots.

|-
| 4:43
| Please note that IPython automatically indents the block.

|-
|4:48
| The four dots tell you that you are inside a block.

|-
| 4:53
| Now type the rest of the <tt>for</tt> loop,

|-
|4:56
|So type print within double quotes Square root of, each, then print within double quotes is comma sqrt in brackets each.

|-
|5:29
| Now we have finished the statements in the block, and still the interpreter is showing four dots, this means that you are still inside the block.

|-
|5:41
| To exit from the block press the return key or the enter key twice without entering anything else.

|-
| 5:50
| It printed the square root of each number in the list, which was executed in the <tt>for</tt> loop.

|-
| 5:57
| Find the cube of all the numbers from one to ten.

|-
|6:01
| But this time let us try it in the vanilla version of Python interpreter.

|-
| 6:07
| Start the vanilla version of Python interpreter by issuing the command <tt>python</tt> in your terminal.

|-
|6:21
|So type for i in range within brackets 1,11 colon

|-
| 6:38
| press enter once, and we will see that this time it shows four dots, but the cursor is close to the dots, so we have to indent the block.

|-
| 6:52
| The vanilla version of Python interpreter does not indent the code automatically.

|-
| 6:58
| So enter four spaces there and then type the following

|-
|7:04
|Then type print i comma within double quotes cube is comma i star star 3. Hit Enter.

|-
| 7:21
| Now when we hit Enter, we still see the four dots.

|-
|7:26
|To get out of the block, hit enter once again.

|-
| 7:32
| Okay!

|-
|7:33
|so the main thing we learnt here is how to use the Python interpreter and the IPython interpreter to specify blocks.

|-
|7:43
|But while we were generating the multiplication table we used something new, <tt>range</tt> function.

|-
|7:50
| <tt>range</tt> function is an inbuilt function in Python which can be used to generate a <tt>list</tt> of integers from a starting number to an ending number.

|-
|7:57
|Note that the ending number that you specify will not be included in the <tt>list</tt>.

|-
| 8:03
| Print all the odd numbers from 1 to 50. Let us do it in our IPython interpreter for ease of use.

|-
| 8:18
| The problem can be solved by just using the <tt>range()</tt> function.

|-
|8:22
|It can be solved as through command line you can type ipython and hit Enter.

|-
| 8:28
| This time we passed three parameters to <tt>range()</tt> function unlike the previous case where we passed only two parameters.

|-
|8:37
|The first two parameters are same in both the cases.

|-
|8:40
|The first parameter is the starting number of the sequence and the second parameter is the end of the range.

|-
|8:45
| Note that the sequence does not include the ending number.

|-
|8:48
| The third parameter is for stepping through the sequence.

|-
| 8:53
| Here we gave two which means we are skipping every alternate element.

|-
|9:03
|So type print range within brackets 1 comma 51 comma 2

|-
| 9:07
| This brings us to the end of the tutorial.

|-
|9:11
|In this tutorial,we learnt to,

|-
|9:12
| 1. create blocks in python using <tt>for</tt> loop

|-
|9:15
| 2. indent the blocks of code

|-
|9:17
| 3. iterate over a list using <tt>for</tt> loop

|-
|9:21
| use the <tt>range()</tt> function

|-
|9:24
| Here are some self assessment questions for you to solve

|-
|9:27
| 1. Indentation is not mandatory in Python

|-
|9:30
| Is it true or false?

|-
|9:33
| 2. Write a code using <tt>for</tt> loop to print the product of all natural numbers from 1 to 20.

|-
|9:39
| 3. What will be the output of-

range within brackets 1,5

|-
| 9:47
| Now, the answers,

|-
|9:48
| 1. False. Indentation is essential in python.

|-
|9:53
| 2. We use the <tt>for</tt> loop in the following manner.

|-
|9:56
| y is equal to 1 for x in range(1,21):

|-
|10:00
| y star is equal to x

|-
|10:03
| then we have to print y

|-
|10:04
| 3. <tt>range within brackets 1,5</tt><nowiki> will produce a list of integers from 1 to 4.</nowiki> that is 1,2,3,4 in square brackets.

|-
| 10:17
| Hope you have enjoyed this tutorial and found it useful.

|-
|10:20
|Thank you!

@@ Line 202: / Line 202: @@
 |-
 | 07:32
-| Okay!
+| Okay! so the main thing we learnt here is how to use the Python interpreter and the IPython interpreter to specify blocks.
-−
-|-
-|07:33
-|so the main thing we learnt here is how to use the Python interpreter and the IPython interpreter to specify blocks.
 |-
@@ Line 233: / Line 229: @@
 |-
-|  08:28
+| 08:28
 | This time we passed three parameters to  range()  function unlike the previous case where we passed only two parameters.
@@ Line 266: / Line 262: @@
 |-
 |09:11
-|In this tutorial,we learnt to,
+|In this tutorial,we learnt to, Create blocks in python using for  loop
-−
-|-
-|09:12
-|Create blocks in python using for  loop
 |-
@@ Line 306: / Line 298: @@
 |-
 | 09:47
-| Now, the answers,
+| Now, the answers, False. Indentation is essential in python.
-−
-|-
-|09:48
-| False. Indentation is essential in python.
 |-
@@ Line 326: / Line 314: @@
 |-
 |10:03
-| then we have to print y
+| then we have to print y range within brackets 1,5  will produce a list of integers from 1 to 4. that is 1,2,3,4 in square brackets.
-−
-|-
-|10:04
-| range within brackets 1,5  will produce a list of integers from 1 to 4. that is 1,2,3,4 in square brackets.
 |-

@@ Line 9: / Line 9: @@
 | 00:07
 | At the end of this tutorial, you will be able to,
 Write blocks of code in python using indentation.
-# Write blocks of code in python using indentation.
+Use the for loop.
-# Use the for loop.
+Use range() function.
-# Use range() function.
+Write blocks in python interpreter
-# Write blocks in python interpreter
+Write blocks in ipython interpreter.
-# Write blocks in ipython interpreter.
 |-
@@ Line 271: / Line 270: @@
 |-
 |09:12
-| 1. create blocks in python using for  loop
+|Create blocks in python using for  loop
 |-
 |09:15
-| 2. indent the blocks of code
+| Indent the blocks of code
 |-
 |09:17
-| 3. iterate over a list using  for  loop
+|iterate over a list using  for  loop
 |-
@@ Line 291: / Line 290: @@
 |-
 |09:27
-| 1. Indentation is not mandatory in Python
+|Indentation is not mandatory in Python
 |-
@@ Line 299: / Line 298: @@
 |-
 |09:33
-| 2. Write a code using  for  loop to print the product of all natural numbers from 1 to 20.
+|Write a code using  for  loop to print the product of all natural numbers from 1 to 20.
 |-
 |09:39
-| 3. What will be the output of-
+| What will be the output of- range within brackets 1,5
-−
- range within brackets 1,5
 |-
@@ Line 313: / Line 310: @@
 |-
 |09:48
-| 1. False. Indentation is essential in python.
+| False. Indentation is essential in python.
 |-
 |09:53
-| 2. We use the  for loop in the following manner.
+| We use the  for loop in the following manner.
 |-
@@ Line 333: / Line 330: @@
 |-
 |10:04
-| 3.range within brackets 1,5  will produce a list of integers from 1 to 4. that is 1,2,3,4 in square brackets.
+| range within brackets 1,5  will produce a list of integers from 1 to 4. that is 1,2,3,4 in square brackets.
 |-

@@ Line 71: / Line 71: @@
 |-
 |  2:24
-| So that was easy!
+| So that way easy!
 |-
@@ Line 79: / Line 79: @@
 |-
 | 2:36
-| Note that here we used two variables,the variable numbers , which is a list,and the other variable <tt>each</tt>, which is the element of list under consideration in each cycle of the  for  loop.
+| Note that here we used two variables,the variable numbers , which is a list,and the other variable each, which is the element of list under consideration in each cycle of the  for  loop.
 |-
@@ Line 176: / Line 176: @@
 |-
 |6:21
-|So type for i in range within brackets 1,11 colon
+|So type for i in range within brackets 1,11 colon and hit enter
 |-
@@ Line 216: / Line 216: @@
 |-
 |7:50
-| <tt>range</tt> function is an inbuilt function in Python which can be used to generate a  list  of integers from a starting number to an ending number.
+|range function is an inbuilt function in Python which can be used to generate a  list  of integers from a starting number to an ending number.
 |-
@@ Line 264: / Line 264: @@
 |-
 | 9:07
-| This brings us to the end of the tutorial.
+| This brings us to the end of this tutorial.
 |-
@@ Line 284: / Line 284: @@
 |-
 |9:21
-| use the <tt>range()</tt> function
+| use the range() function
 |-
@@ Line 334: / Line 334: @@
 |-
 |10:04
-| 3. <tt>range within brackets 1,5  will produce a list of integers from 1 to 4. that is 1,2,3,4 in square brackets.
+| 3.range within brackets 1,5  will produce a list of integers from 1 to 4. that is 1,2,3,4 in square brackets.
 |-

@@ Line 11: / Line 11: @@
 # Write blocks of code in python using indentation.
-# Use the <tt>for</tt> loop.
+# Use the for loop.
-# Use <tt>range()</tt> function.
+# Use range() function.
 # Write blocks in python interpreter
 # Write blocks in ipython interpreter.
@@ Line 23: / Line 23: @@
 |-
 |0:31
-|In Python whitespace is significant, and the blocks are visually separated.
+|In Python white space is significant, and the blocks are visually separated.
 |-
@@ Line 43: / Line 43: @@
 |-
 | 1:08
-| Now let us move straight into <tt>for</tt> loop.
+| Now let us move straight into  for  loop.
 |-
@@ Line 51: / Line 51: @@
 |-
 | 1:37
-| For the problem, first we need to create a <tt>list</tt> of numbers and then iterate over the list and find the square root of each element in it.
+| For the problem, first we need to create a list  of numbers and then iterate over the list and find the square root of each element in it.
 |-
@@ Line 79: / Line 79: @@
 |-
 | 2:36
-| Note that here we used two variables,the variable <tt>numbers</tt>, which is a list,and the other variable <tt>each</tt>, which is the element of list under consideration in each cycle of the <tt>for</tt> loop.
+| Note that here we used two variables,the variable numbers , which is a list,and the other variable <tt>each</tt>, which is the element of list under consideration in each cycle of the  for  loop.
 |-
@@ Line 87: / Line 87: @@
 |-
 | 2:52
-| Note that the lines after <tt>for</tt> statement, is indented using four spaces.
+| Note that the lines after  for  statement, is indented using four spaces.
 |-
@@ Line 99: / Line 99: @@
 |-
 |3:10
-| Also, the fourth line or the immediate line after the <tt>for</tt> block is not indented.
+| Also, the fourth line or the immediate line after the  for  block is not indented.
 |-
 | 3:18
-| It means that it is not a part of the <tt>for</tt> loop and the lines after that dont fall in the scope of the <tt>for</tt> loop.
+| It means that it is not a part of the  for  loop and the lines after that don't fall in the scope of the  for  loop.
 |-
@@ Line 144: / Line 144: @@
 |-
 |  4:53
-| Now type the rest of the <tt>for</tt> loop,
+| Now type the rest of the  for  loop,
 |-
@@ Line 160: / Line 160: @@
 |-
 | 5:50
-| It printed the square root of each number in the list, which was executed in the <tt>for</tt> loop.
+| It printed the square root of each number in the list, which was executed in the  for  loop.
 |-
@@ Line 172: / Line 172: @@
 |-
 | 6:07
-| Start the vanilla version of Python interpreter by issuing the command <tt>python</tt> in your terminal.
+| Start the vanilla version of Python interpreter by issuing the command  python in your terminal.
 |-
@@ Line 212: / Line 212: @@
 |-
 |7:43
-|But while we were generating the multiplication table we used something new, <tt>range</tt> function.
+|But while we were generating the multiplication table we used something new,  range  function.
 |-
 |7:50
-| <tt>range</tt> function is an inbuilt function in Python which can be used to generate a <tt>list</tt> of integers from a starting number to an ending number.
+| <tt>range</tt> function is an inbuilt function in Python which can be used to generate a  list  of integers from a starting number to an ending number.
 |-
 |7:57
-|Note that the ending number that you specify will not be included in the <tt>list</tt>.
+|Note that the ending number that you specify will not be included in the list
 |-
@@ Line 228: / Line 228: @@
 |-
 | 8:18
-| The problem can be solved by just using the <tt>range()</tt> function.
+| The problem can be solved by just using the  range()  function.
 |-
@@ Line 236: / Line 236: @@
 |-
 |  8:28
-| This time we passed three parameters to <tt>range()</tt> function unlike the previous case where we passed only two parameters.
+| This time we passed three parameters to  range()  function unlike the previous case where we passed only two parameters.
 |-
@@ Line 272: / Line 272: @@
 |-
 |9:12
-| 1. create blocks in python using <tt>for</tt> loop
+| 1. create blocks in python using for  loop
 |-
@@ Line 280: / Line 280: @@
 |-
 |9:17
-| 3. iterate over a list using <tt>for</tt> loop
+| 3. iterate over a list using  for  loop
 |-
@@ Line 300: / Line 300: @@
 |-
 |9:33
-| 2. Write a code using <tt>for</tt> loop to print the product of all natural numbers from 1 to 20.
+| 2. Write a code using  for  loop to print the product of all natural numbers from 1 to 20.
 |-
@@ Line 318: / Line 318: @@
 |-
 |9:53
-| 2. We use the <tt>for</tt> loop in the following manner.
+| 2. We use the  for loop in the following manner.
 |-
@@ Line 334: / Line 334: @@
 |-
 |10:04
-| 3. <tt>range within brackets 1,5</tt><nowiki> will produce a list of integers from 1 to 4.</nowiki> that is 1,2,3,4 in square brackets.
+| 3. <tt>range within brackets 1,5  will produce a list of integers from 1 to 4. that is 1,2,3,4 in square brackets.
 |-