Print ufloat variable name and value, not representation

Question

There is a useful recent feature in python allowing one to print a variable's name and its value: https://stackoverflow.com/a/57225950/6843348. This doesn't quite work with the uncertainties library's ufloat type, because the representation is printed, losing the formatting. Any suggestion to work around this?

from uncertainties import ufloat

x = ufloat(1.8768768, 0.0039788594)
print(x) # OK: 1.877+/-0.004
print(repr(x)) # 1.8768768+/-0.0039788594
print(f"{x=}") # Not OK: x=1.8768768+/-0.0039788594

EDIT Would prefer to enter the var name only once, and keep ufloat's formatting

Perhaps a question for https://stackoverflow.com/users/42973/eric-o-lebigot — Mister Mak, May 28 '23 at 13:50

score 0 · Answer 1 · answered May 26 '23 at 20:29

0

Change your print statement to:

print(f'x={x}')

answered May 26 '23 at 20:29

David Rosario

122
2

Thanks! That sort of solves it, but is clunky in the sense you need to enter the variable name twice. Can it be simplified? – Mister Mak May 26 '23 at 20:37
I was unable to find a more concise alternative. – David Rosario May 26 '23 at 21:14

score 0 · Answer 2 · answered May 26 '23 at 20:57

I HOPE YOU ARE DOING GREAT!!! While using f-strings to print the variable name and its value with uncertainties' ufloat type, you can define a custom function that extracts the nominal value and standard deviation separately. FOR EXAMPLE:

from uncertainties import ufloat

def print_ufloat(var_name, value): nom_value = value.nominal_value std_dev = value.std_dev

print(f"{var_name}={nom_value:.3f}+/-{std_dev:.3f}")

x = ufloat(1.8768768, 0.0039788594) print_ufloat('x', x)

Using this custom function, you can preserve the desired formatting for printing variable names and their values when working with uncertainties' ufloat type.

Thanks! My impression is your solution requires to enter the var name and value, and overrides ufloat's formatting. Have edited question to clarify that point. — Mister Mak, May 26 '23 at 21:30

Print ufloat variable name and value, not representation

2 Answers2