How to print list of numbers in blocks?

Question

Hello there,

Can someone advise or hint on how I can use a simple loop to print a randomized list of 16 numbers in a 4 x 4 matrix? My code Is as attachéd.

Thanks and Regards
Ben

https://code.sololearn.com/c4L2lirX6J7K/?ref=app

Answer 1

Check this code you can use numpy for this.

https://code.sololearn.com/cl3q5hIjjt4B/?ref=app

Answer 2

[print(*myList[x:x+4]) for x in range(0,len(myList),4)]

Answer 3

myList = list(range(1,17))
matrix = []
for i in range(0,len(myList),4):
matrix.append(myList[i:i+4])

for i in matrix:
print(" ".join(str(j) for j in i))

"What is a docstring?"
https://www.sololearn.com/learn/JUMP_LINK__&&__Python__&&__JUMP_LINK/2288/

Answer 4

Ben why do you want this exactly same output,but in your code list is rearranging differently at every execution due to random module.

Answer 5

hi @Cbr, what is a doc string?

Answer 6

@diego, thabks for the help. but im looking for a result like this:
5 7 15 1
8 16 6 2
4 9 10 11
12 14 13 3

Answer 7

Maninder $ingh i dont need this exact same output, it is just an example of what I need. i have just tried your code, the output seems to be what i need! :) thank you!

Answer 8

Diego your code doesn’t seem to work?

Answer 9

Diego i see, ive tried and it works! ill need some time to understand the .append method, it seems you have create lists within a list! its really a cool solution!

thank you so much for the help!

Answer 10

Diego may i know what is the meaning of this part you wrote:
for i in matrix:
print(“ “.join(str(j) for j in i))

in particular the part “for j in i”, what does this mean?

Answer 11

It's called a list comprehension. Here's a great tutorial about it:
https://code.sololearn.com/ck6HicJ6Z8jG/?ref=app

If you have any more doubts you can always message me (if you're on Android).

Answer 12

Louis thank you for such an elegant solution!

why is it possible to add a for loop after the print function?

Answer 13

hi guys, played around abit with @louis code, and this is the format i understand and works:
for x in range(0,len(myList),4):
print(*myList[x:x+4])

one question: why does the “*” magically removes the “list brackets [ ]”?

Answer 14

hi guys, played around abit with @louis code, and this is the format i understand and works:
for x in range(0,len(myList),4):
print(*myList[x:x+4])

one question: why does the “*” magically removes the “list brackets [ ]”?

Answer 15

Ben It's the power of list comprehensions.

The "*" is unpacking the elements of the list. If you use it inside the print() function you won't be passing a list as argument, but the elements inside it.

print(*[4, 2]) # 4 2
print(4, 2) # 4 2

https://www.sololearn.com/learn/JUMP_LINK__&&__Python__&&__JUMP_LINK/2485/