Force Python To Print A Certain Number Of Decimal Places

I have a python program which takes some floating type values and writes to a file. I round these numbers to 6 decimal places and then convert to a string type before writing to fi

Solution 1:

You can use the f-string f'{value:.6f}'.

Example:

value = 0.234
print(f'{value:.6f}')

value = 1
print(f'{value:.6f}')

value = 0.95269175
print(f'{value:.6f}')

Output:

0.234000
1.000000
0.952692

Also, in the answer linked in a comment, there was reference to :g. That can work, but probably not in this situation, because g may print scientific notation where appropriate, and discards insignificant zeroes. Consider a slightly modified example using g:

value = 0.234
print(f'{value:.6g}')

value = 1
print(f'{value:.6g}')

value = 0.000000000095269175
print(f'{value:.6g}')

Output:

0.234
1
9.52692e-11

Solution 2:

You can also use basic string formatting:

a = 3e-06

# Outputs 0.000003
print('%.6f' % a)

# Outputs 0.000003000000
print('%.12f' % a)