django float round tripping

Robin Becker robin at reportlab.com
Fri Apr 7 06:41:56 EDT 2017


I've been having problems with django FloatFields not round tripping properly; eg

field = 0.018903438896219302

gets saved and returns as

0.0189034388962193

It turns out that this is a property of the MySQLdb python interface where in 
converter.py we have the definition

def Float2Str(o, d):
     return '%.15g' % o

if I change this to

def Float2Str(o, d):
     return repr(o)

I do seem able to get reproducibility.

Are there any downsides to making this change?
-- 
Robin Becker



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