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In this tutorial we will talk about Paul a use for iterating over a set of statements repeatedly in

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Python.

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There are three types of Lew The for loop while and do y Lew a for loop is used for either dating or

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what a sequence such as this a string a tuple or addiction.

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And this is the syntax for the for loop for variable in sequence and we have a set of statements after

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the colon so if you want to either iterate or what each of the characters in a string you can use the

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for loop.

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So here I have used a far loop to either did or what a string for i in Python.

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And then like we do for it and if statement or the if clause use goal in here and then I have a print

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statement indeed for loop as you can see we have indented the statement in default loop like we do for

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it.

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And if clause with the for loop we can execute a set of statements for each item in a list.

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Tuple set out a string.

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Now let's consider the second example here in this example I want to I did it or would a list.

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So this is the statement that I'm going to use for x in this particular list containing the elements

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1 2 3 4 5 so for all elements in the list I want to squared each of the items and then print the result

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here.

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So for each item in the list this action is performed.

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And then finally it this printed the items of the sequence object are assigned one after the other to

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the loop variable that is in case of our example the item in the string that is B and Y.

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D hedge or n are assigned to the loop variable ie in a sequence first it points to the element B and

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then it goes to Y and then t h and so on so to be precise the variable points to the items and for each

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item the code in the for loop that executed.

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So in the second example the loop variable X points to 1 first and then it moves to the second item

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2 and then 3 and so on but let's look at two examples in the Jupiter note so in order to iterate over

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the elements in the string I'm going to use the for loop.

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And finally I'm going to print all of the elements in the string so let's execute this cell.

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So the far loop has used do loop bearable to pick each of the elements in the string and then in the

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body or the for loop we wanted to print each of these elements.

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Now let's look at another example.

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The for loop is going to pick each item in the list and apply the same set of statements for each item

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in the list.

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So another example it's going to pick the item one graded and then print the result it's going to Big

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D second item two squared in number two and then print it as well.

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And so on.

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Not let execute the cell so as you can see the same set of statements have been applied on each element

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of the list.

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In the second example I have passed the Range object to the list constructor and using the for loop

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I am going to iterate over the D sequence of items in the list fort I in list and I have passed the

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argument range of 10 and in the for loop body I'm going to put in the items in the list.

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So after I execute this said for loop has printed the items in the list beginning from 0 to 9.

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Coming back to the for loop for loop can have an optional X block both related with it and the 8 block

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executes only when the for loop has executed all the iterations.

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So in this example I have used an alias block along with the for loop and the L statement is executed.

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Then the for loop has exhausted either dating or were the items in the or the element in the string.

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The IDS blog it executed with de loop I iteration complete normally.

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So let's execute this piece of code in the Jupiter notebook.

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Here in this example we are using an edited block with a for loop using the loop where it will go into

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irate all the items in the trim print the items and after I iterating all over all the items in the

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string the control goes to the else blog and the statement in the else block executed.

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So when you execute this piece of code you have the items in the string printed first all of the items

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and finally the print statement in the edit block is printed.

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Next we're going to discuss about nested loops for loops present inside and not good for loop then it

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does call a nested for loop when units do lose the outer loop takes control of the number of complete

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iterations of the inner loop.

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So let's understand this

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so here is an example demonstrating nested loops.

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So this is loop and Mike loop I've used a range function to generate the numbers and this range function

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is going to generate the numbers 0 1 and 2 next.

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This is the inner loop the inner loop I'd read or would a string containing the characters a B and C

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so the inner loop has a print function that brings each of the elements.

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And finally after we come out of the inner Lew I have given a print function for every single ideation

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of the outer loop several ideations of the inner loop performed for one ideation of the outer loop.

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The dire cycle of ideations is completed in the inner cycle.

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This piece of code meaning the inner loop print the elements a b and c.

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So this completes one cycle of the inner loop.

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And here I have given a print function to show you that the outer loop has completed only the first

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ideation.

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So this brain function is going to print this text like this zero times and then the control goes back

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to the inner loop again.

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The second cycle again print a B and C and now control comes to the outer loop one time

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and then so on.

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So this is the first cycle.

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Second cycle and we have three such cycles like that so let's execute this piece of code in the Jupiter

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notebook.

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So as this goes to earlier I have used two loops to demonstrate nested loops for one cycle.

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That is for one complete iteration of the inner loop.

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One ideation of the outer loop is performed let's execute this piece of code the inner loop has rendered

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the each of the characters in the string ABC.

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The first itemization of the outer loop print this text next.

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The second cycle.

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Comprising of three ideations of the inner loop is executed and then we have the second by iteration

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of the outer loop.

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Printing this text next again the third cycle of the inner blueprint.

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This text A B and C.

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And finally we have the outer loop printing text here which is the final iteration.