Python - Converting String Numbers To Float

Question

I want to convert string numbers on a list to float numbers and i can't do it, so i need some help.

num = '0.00003533'

print('{:f}'.format(float(num)))

formatting it without decimals, only returns a float of 0.000035, i need the entire string in a float.

print('{:8f}'.format(float(num)))

adding the exact decimal works, but the numbers in the list with decimals varies greatly, so i can't manually add it everytime, how could i automatically add the correct decimal number inside the format? something like '{':exactdecimalf'} exactdecinal being a variable.

i'm using a module that requires float, which is why i can't print it directly from the string format.

please be clear add one example of your input and output that you want — nishant, Feb 16 '19 at 18:55
Why not just `print(float(num))` just `float(num)` alone I believe does what you’re asking.. — Jab, Feb 16 '19 at 18:57
Keep it as a string if you want to print it the way it was, and convert it to a float only for numerical operations. But be aware of [floating point gotchas](https://stackoverflow.com/questions/588004/is-floating-point-math-broken) — Thierry Lathuille, Feb 16 '19 at 18:57

score 0 · Answer 1 · answered Feb 16 '19 at 19:00

0

Maybe double precision will suit you.

from decimal import Decimal
print ('{:f}'.format(Decimal(num)))

answered Feb 16 '19 at 19:00

Tajinder Singh

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score 0 · Accepted Answer · answered Feb 16 '19 at 19:00

0

Use this

from decimal import Decimal
num = '0.00003533'
print(Decimal(num)) #0.00003533

if you want to print as string

print ('{:f}'.format(Decimal(num)))

answered Feb 16 '19 at 19:00

nishant

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score -1 · Answer 3 · answered Feb 16 '19 at 18:59

-1

You can split the string and take the length of the last part with

len(num.split(".")[1])

Then use that as the number of decimals.

answered Feb 16 '19 at 18:59

mfp2001

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Python - Converting String Numbers To Float

3 Answers3