How can I remove the 'none' out of the output?

Question

I was supposed to make a diamond out of this and I have successfully done so but I have a problem. Here is my code

k = 7
def triangle(k):
    a = (2*k) -1
    k = 3
    for x in range(0,a+1):
        if x % 2 != 0:
            f = int((a - x)/2)
            g = f"{'#'*f}{'*'*x}{'#'*f}"
            print(g)
def diamond(k):
    a = (2 * k) - 1
    k = 3
    for x in reversed(range(0, a)):
        if x % 2 != 0:
            f = int((a - x) / 2)
            g = f"{'#' * f}{'*' * x}{'#' * f}"
            print(g)

l = f"{triangle(k)}\n{diamond(k)}"
print(l)

Along with the diamond, there are also two 'none' appearing underneath like this in the output..

######*######
#####***#####
####*****####
###*******###
##*********##
#***********#
*************
#***********#
##*********##
###*******###
####*****####
#####***#####
######*######
None
None

How can I print the output without including the none in the output??

Neither functions return anything, so capturing and printing their calls makes little sense — DeepSpace, Oct 12 '21 at 14:03
`triangle(k)` and `diamond(k)` both don't return anything (i.e. they return `None`). Instead, they contain print statements. So when you do `print(l)` you're printing `"None\nNone"` — Green Cloak Guy, Oct 12 '21 at 14:03
What's the point of `l = f"{triangle(k)}\n{diamond(k)}"; print(l)`? Calling `triangle` and `diamond` already prints the results — ForceBru, Oct 12 '21 at 14:04
I tried not printing it but the result is wrong though, like the figure is distorted when I try it... is there any part of my code that I should change to make sure the 'none' doesnt get printed?? — Nutnicha, Oct 12 '21 at 14:08
Does this answer your question? [Why is this printing 'None' in the output?](https://stackoverflow.com/questions/28812851/why-is-this-printing-none-in-the-output) — Tomerikoo, Oct 12 '21 at 23:20

score 0 · Answer 1 · answered Oct 12 '21 at 14:12

Calling the functions already prints the output. Printing the return values (None) makes little sense. That being said, this can be tremendously simplified:

def up_and_down(n):  # 1,2, ..., n, ..., 2, 1
    return (*range(1, n), *range(n, 0, -1))

def diamond(n):
    for i in up_and_down(n):
        print((n-i)*'#', *('*' for _ in up_and_down(i)), (n-i)*'#', sep='') 

>>> diamond(7)
######*######
#####***#####
####*****####
###*******###
##*********##
#***********#
*************
#***********#
##*********##
###*******###
####*****####
#####***#####
######*######

where should I put this in my code though?? Like can u please copy and paste my code and then show where to put your piece of code please?? — Nutnicha, Oct 12 '21 at 14:22

rv.kvetch · Accepted Answer · 2021-10-12T19:02:17.920

0

Here's a modification on @schwobasggl's answer, using f-strings that works in Python 3.6+

def up_and_down(n):  # 1,2, ..., n, ..., 2, 1
    return (*range(1, n), *range(n, 0, -1))


def diamond(n, pad='#', fill='*'):
    w = (2 * n) - 1

    for i in up_and_down(n):
        # you can also use the below, but it's slightly less performant:
        # fill_w = len(up_and_down(i))
        fill_w = i * 2 - 1

        print(f'{fill * fill_w:{pad}^{w}}')

It should end up with the same result:

>>> diamond(7)

######*######
#####***#####
####*****####
###*******###
##*********##
#***********#
*************
#***********#
##*********##
###*******###
####*****####
#####***#####
######*######

If you want to print a triangle (the top half of the diamond), you can iterate over only the first half of up_and_down in the outer loop. Another way is to just iterate over range(1, n+1) - that is 1, 2, 3 for n=3 - as shown below:

def triangle(n, pad='#', fill='*'):
    w = (2 * n) - 1

    for i in range(1, n + 1):
        print(f'{fill * (i * 2 - 1):{pad}^{w}}')

It looks like that should now work to print just the top half of the diamond above:

>>> triangle(7)

######*######
#####***#####
####*****####
###*******###
##*********##
#***********#
*************

Links for reference

edited Oct 12 '21 at 19:02

answered Oct 12 '21 at 14:35

rv.kvetch

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your code is great, but what if I want to print the top half only, aka I want to print a triangle as well under -- def triangle(n): so is there a way for me to halve the diamond?? – Nutnicha Oct 12 '21 at 14:42
@Nutnicha hmm, that should be possible with a slight change. let me take a look. – rv.kvetch Oct 12 '21 at 14:43
yepp, pls lemme know when u modified it, thx a lott – Nutnicha Oct 12 '21 at 14:44
@Nutnicha I updated answer above with a `triangle` function you can use to print the top half of a diamond – rv.kvetch Oct 12 '21 at 14:50
1

Thank you very very much – Nutnicha Oct 12 '21 at 14:57
@Nutnicha no problem! remember to also accept an answer if you find it helpful, so that it can help others who might be searching for a similar problem. – rv.kvetch Oct 12 '21 at 15:21

How can I remove the 'none' out of the output?

2 Answers2

Links for reference