[SOLR-16361] 'mod' function query casts to float, returns wrong modulus for large ints

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 9.0
• Fix Version/s: 9.1, main (10.0)
• Component/s: search
• Assignee: Eric Pugh
• Reporter: Dan Rosher
• Created: 30/Aug/22 10:44
• Updated: 25/Jan/23 16:15
• Resolved: 16/Sep/22 19:49

Description

mod function query uses DualFloatFunction. This eventualy does a conversion

 (float)value 

converting an integer (32bit) into a float which has a 24bit mantissa ,resulting in a loss of precision.

This means that for integers > 2^24 this returns an incorrect modulus due to this loss of precision.

Should we use integer only, or perhaps cast to double (so then create a DualDoubleFunction) which has a 52bit mantissa, so can convert int to double without loss of precision?

This issue may also affect the other function queries?

 

Issue Links

• links to: GitHub Pull Request #989