Is it possible to filter out zero values in formatted string literals?-CodePudding

Formatted string literals (: ) are used to show the sign of a number ( or -). e.g:

a = 2

b = -5

print(f"{a b: }")

output: -3

a = 2

b = 5

print(f"{a b: }")

output:  7

If the output is 0, it is given as 0.

Is there a way in which if the sum of a and b is 0, the output should return nothing (I'm not sure what that would mean), or maybe output an empty string?

Example: Gn = c (a-b)

If a is 3 and b is 3 as well, the output should be Gn = c. Not Gn=c 0

I have tried to apply some conditional statement wrt 0, to return an empty string instead but Formatted string literals (: ) only work on integers.

CodePudding user response：

Is there a way in which if the sum of a and b is 0, the output should return nothing (I'm not sure what that would mean), or maybe output an empty string?

Make a format helper. Non-zero is considered True, so you can return an empty string if the number is false:

def fmt(i):
    return f'{i: }' if i else ''

a = 1
for b in range(3):
    print(f'result: {fmt(a-b)}')

Output:

result:  1
result: 
result: -1

CodePudding user response：

I'm not sure I'm totally following, but in your case, maybe just do the computation and branch on that:

c = 1
a = 2
b = 3
a_minus_b = a - b
if a_minus_b:
    print(f"Gn = {c}   ({a} - {b})")
else:
    print(f"Gn = {c}")

Of course this could be done more fancily (if less readably), e.g.

print(f"Gn = {c}   ({a} - {b})" if a_minus_b else f"Gn = {c}")

print(f"Gn = {c}"   f"   ({a} - {b})" if a_minus_b else "")

CodePudding user response：

You could insert a conditional statement to check sum of both variables, and if if the sum is zero you can print an empty string literals or else you can print the actual value.

a = 2
b = -3

if a   b == 0:
    print(f"")
else:
    print(f"{a b: }")