[Tutor] How does the interpreter determine how many decimal places to display for a float?

[Peter Otten]

On 15/05/2021 05:29, boB Stepp wrote:

> How does >= Python 3.1 determine the "shortest of these"?

This is an interesting question...

A little digging in the Python source turns up

https://github.com/python/cpython/blob/main/Python/dtoa.c

Does that answer your question? Well, it didn't help me, so I looked for 
the original code and found what seems to be the corresponding paper

David M. Gay:
Correctly Rounded Binary-Decimal and Decimal-Binary Conversion
https://ampl.com/REFS/rounding.pdf

which in turn leads to

Guy L. Steele Jr., Jon L White:
How to Print Floating-Point Numbers Accurately

https://lists.nongnu.org/archive/html/gcl-devel/2012-10/pdfkieTlklRzN.pdf


Hope that helps ;)