#26 Python Tutorial for Beginners | Array in Python

[Music] welcome back aliens my name is Ivan 20 and let's get into this series on Python in this video we're going to talk about arrays now we have worked with least we have work with tuples and now we know how all those things works so if you want to have a list of values with you of course you can go with least or if you want to make it constant you can go for tuple now while added them now in anak we need to have all the values of same time so we can have the same list with integer float and string in one list but that's not the case with array so a days are similar to list but with one difference that you need to have all the values of same time so if you say it's an int array should be of int array if you say it is floated it all the value should be float there's one advantage here and is in Python they don't have specific size they don't have a fixed size which means you can expand you can shrink it example let's say you have five values and if you think hey we want 10 the end user can expand it and if you feel hey we have 10 values but we need only four values now we can shrink it so it is quite flexible to work with and it offers you certain methods to work with example if you want to add an image you can use append if you want to find a particular element you can use other methods in fact we have a vertical as index using which you can get the index number of a particular value Oh hold on we'll do it we'll do that in the practical video here now basically when you will be using array so think about this let's say if you have a list of students right and then in that so every should you will have a marks so let's say we have one subject which is let's say Python itself so it's a language and you have a subject in your college and of course a view will be having a box so if you have ten students in a class you you need to create ten different variables like marks one marks two mouths three or let's say if you have hundred students need to create 100 variables now instead of doing that we can create an array right now how do we do that so in order to use array we will be using array but then the problem is we will not be getting this array by default right okay so we need to import a module called as a date to use this so how would you do that you will say import add it right so this is up to use I have to say import and in this module array we have a function called as Adi so we have to say Eddie dot added this is how you create an ID I know it's a lot of edits there so if you don't want to use this edit every time you can also use array so you can say import Eddie as a so instead of using and every time you can say a dot added this one way so again you can use edit or add it by inputting array or you can say input array as arr which is you're using Eliza and then you can say a RR dot Eddie now if you if you just want to avoid everything you can simply use we have done that before right so if you want to work with modules if you want to import modules you can say from add a input now you can specify the functions you want to work with or you can simply specify stars so star means you want to work with all the functions right now once you once you have this function array now let's see how do you get an adding so I want to create a day off let's label not go for Mark's here let's go for girls now valence is basically values okay so it's it's short form for values now I want to create an array with with the name of Val's so you have to say adding now we have to specify two things the first thing that you specify is the type and the second time second you have to mention is the values now why time because in adding all the values should be of same type right so if you say hey we have int added you have to mention that it's an Inc added if it is a float adding up to mention that how do you do that okay if you have to you some keywords right example we can say ain't float but that that is not how it works here so you have to use a type code now what it means every time will have a unique code okay example for integer in fact anything integers as well we have different types of integers we have bite we have long and we have eight when you work with different language like C C++ Java we have these types there's right we have bite we have long we have int same way in here in Python we also have int now depends upon you know the moment you change the type it will change the size in the memory example if you want to say hey I want a smaller integer you can say bite because by a small integer it takes only one byte there are the one is normal which which we'll take two bites and then we have long integer which will take four bites now what if you want to have float values for that we it will take any four bytes so it is f float which is which will take four bytes in fact double as well so we have double float which is which will give you more memory of eight bytes what if you want to go for character for that you have to use U which is Unicode right and it takes two bytes okay because you need Unicode need two bytes to store data okay that works now the question is what if you want to have unsigned integer nobody is an unsigned I signed so let's say if you if you're going for non integer it goes from a negative range to a positive positive range right what did you don't want to store a negative value in that case you will be going for unsigned integer because it starts with 0 and ends at a particular value so we will not be considering negative numbers here right and you can see the table we have all the time so if you want to work with unsigned integer you have to use capital I if you want to use sign integer which is long one you can use small L right so you can you can defer this table and we'll be using that here so I want to create a day of integers and the way you can do that is by saying aye because you are using an integer array and you can give up comma and you have to mention a square bracket because that's how you represent arrays now in this square bracket you can mention values I will go for simple values here just to you know make it simple so I will say five nine eight four and two simple values we got five values here and once you've got this add you can print it and how do we print it it's very easy you will say print and you will print the values here will say Val's now for this code you can see record an array it's so simple right we can't you can see this printing array of type int and then you got the values okay now let me just do a twist here what if if I put a different value example here instead of having eight let me say eight point five now you can see this is where it all starts and if I love this code you can see record an error Heather says integer argument expected got float can you see that here so this is the taller we have right when you say it is integers and if you are trying to put float that will not work so of course you have to go for integers can I have negative values of course we can have because small I means signed integer which stands to negative value to positive values we'll work let me just run this code so it works you can have negative values but what if I say capital I which means you cannot have negative values now and the moment is on this code you can see we got an error it says cannot convert negative value to unsigned int right to this important remember so when you tell an array you have to make sure that you specify a proper type code okay now once we have done with that in a day as we are working with a DS now we can use certain functions example if I say values dot so enough market function is buffer info now before info will give you this size of the adding right so if I say okay we were supposed to change this I small I saw that with me under this code and you can see we call it something now it is did something so this is a tuple here with two two things the first one is the address so this is the address of your array and the second parameter there is actually your size which is fine right if I change the number of elements here if I remove two of course you will be getting four and is now 74 right so that's how you can work with before info in fact we have some other methods as well I would say value start in fact we also have type code which will print the type of the code you're working with which is int in this case so you can say this I which is integer this was the property here now what if you want to add a value you can use append what if you want to remove a value you can use remove you if you want to reverse the IDL added you can do that here example let's try so if I said reverse and if I print the values and if I save 10 because reverse doesn't written value so if you want to work with reverse you have to save Val's dot reverse and you can see first you got the adding it will reverse the area it will give you the value so if I say shift f10 you got the value which is array and then two phone so you can see all the values got reversed but the point is what if I don't want to print all the values as it is I want to print the values one by one is it possible of course why this is added and when you say a date is similar to list so we can use index numbers right index number start with 0 right so we can use index number to print one value so I would say values off and I want to say 0 now when I say values of 0 it will print the first value right in this case it is - okay why - because we are the buzzing it right because after he was saying to will come first let's remove that and because I don't want to reverse now let's let's say run and you can see we got five if you change this value to let's say let's say one it will print nine but I want to print all the values not just one or two values right in this case we will be using a loop your favorite loop you can work with while loop you can work with for loop your wish okay here I will go for look for no because for loop makes sense when you know this range so it's saying for I in when in in fact I'll be using range I will start with the range which go till four or five because we have five values right so range will start with zero it will end that four and every time this loop runs I have to say I now there are two things which are missing in this loop the first one is the colon right and the second thing is this print belongs to a for loop so you have to give a tab a proper indentation right and now let's run this code and you got the value which is five nine minus eight four and two so it's so simple so this is how you do print all these values here so this is fun white so you can played all the values one by one it's like we have one more way so if you don't so what is happening here is the value of I is changing from 0 to 4 every time you long this school it will say values of 0 values of one values of two but what if you don't know this length of it because here we know it's five you can see that but right what if you don't know the length or if you want to make it more dynamic in that case you can say length of Val's so length of valves will give you the length and you can pass that length in range right so indirectly you know at one time it will be range five right because size is five and it works now this this is one another way of printing all what you can do is instead of saying range you can directly save Val's so I will say for e even I works but then I would say for e in Val and I can drag the print the value of e so fall is very dynamic you know so sometime you can use for with range which will go for index values or here it will die agree go for the values so in Val's we have five nine minus eight four nine two so it will fetch the value one by one so II will left four to five then evil therefore to nine then you will refer to -8 so your choice the way you want to work with it 74 on this code it still works okay so this this thing is working now can I walk with characters because we have seen how to work with integers we can also use float here can I work with characters of course you can so what if you do is instead of saying I you have to say you which is Unicode you can say characters and here instead of having numbers we should be using characters I would say single quote a single code E and then single code I so we have AE i and then i find on this code you can see we got the same values so yes you can work with unique codes as well look at this thing works no what do I do is I will just undo it and I will go back to et just because I want to do some one small operation okay so what I want is I want to create a new adding ok with the same values example I will just I will just take positive values now 5 9 8 4 2 I want to create a new array with the same values is it possible of course you can do it right you can say a new array here I will say new array and equal to you can see the same thing you can say array and then I then comma you can put the same values but they should doing that what you can do is you can say a D bracket and in this bracket you can mention hey I don't know the type C when you know the type is I you can do it here when you know the values you can type it here but sometimes you want to copy it right maybe you're getting this values from somewhere else in that case you cannot simply type the values right so in that case you can say I don't know the type just take the type from Val's and shop saying oh you're simply saying type code from Val and then the values now I donate the values so you can see now we have a different syntax here try to understand this so what we are saying is hey I don't know the values but take the values from Val's so they devalues a now able that wasn't one that anytime a for a in Wells so what will happen now is it will so so this for loop will take one one value from Val's and it will assign to the array so it will say hey I got five assigned I got nine assigned so that one day which is getting up is coming in to a and then just getting assigned to the new array just to prove my point I will ensure printing the Bastile print a new added here let's run this boot and you can see record the values so the all the array values are coming into new adding so syntax is first of all good to mention hey I don't need the type of it get the type from the old array which is Val's and then the second one where we are mentioning here is the loop so we are saying hey I don't know the values what you can do is take one one value from Val's and you can do that with the I'll go for look right so you're saying for a in Val's and then it will fetch one more value we are assigning it to be added it works in fact you can do one more thing you should of assign the same value what if you want to assign the square of it example I want to assign 2581 and so on I want to assign the square of a number in that case you can simply say a into a so you're simply creating a square of a number let's run this code and you can see record values we got 25 81 6469 4 so you are getting this square of a number so it's so simple to do all the stuff in Python you know if you do want to do the same thing in other languages you have to write multiple lines of code and that's why we say you know in Python you can do multiple things in less number of lines now what if you want to print this values using while loop again we have done with for it so we know how it works can use while loop here of course we can you know a lot of people have this confusion with fall and while you can use while loop here as well no but the thing is for while loop you have to use three steps right you have to use initialization you have to check for the condition and you have to do increment agreement by yourself so let's do that so we say I is equal to zero if you have to check for the conditions I will say while I less than length of newarray because I don't know the length of newarray : and then here you will say print the value print new array and then we have to use index values so we have to say new array I and once you have printer you have to do increment or decrement because here we have to use increments I will say I plus equal to one so the thing is you can do it but the only thing is you have to do it manually and you can see it works and I know in this case for loop makes more sense right because you don't have to initialize you don't have to increment decrement and you don't even have to check whether conditions right what you can use while loop so don't about the bow to Eddie's in fact we have so many things to work with Alice now so in this video we have talked about the basics of adding how can you create an array and how can you print the values how can you create a different area from from the existing addy so that's it from this video I hope you enjoyed this series let me know in the comment section do click the like button if you enjoy any times for watching everyone bye bye you

Channel: Telusko

Views: 774,963

Rating: 4.8955789 out of 5

Keywords: telusko, navin, reddy, tutorial, java, python, array, advantage, why, need, when, use, create, import, module, type, type code, data type, store, print, value, buffer, buffer_info, reverse, function, index, loop, length, copy, unicode, copy data type

Id: 6a39OjkCN5I

Length: 15min 57sec (957 seconds)

Published: Wed Jul 18 2018