[MATH-1070] Incorrect rounding of float

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 3.2
• Fix Version/s: 3.3

Environment

Windows 7, IntelliJ IDEA 10.5.4.

• Assignee: Unassigned
• Reporter: Oleksandr Muliarevych
• Created: 03/Dec/13 12:31
• Updated: 19/May/14 15:13
• Resolved: 09/Jan/14 13:18

Description

package org.apache.commons.math3.util
example of usage of round functions of Precision class:

Precision.round(0.0f, 2, BigDecimal.ROUND_UP) = 0.01
Precision.round((float)0.0, 2, BigDecimal.ROUND_UP) = 0.01
Precision.round((float) 0.0, 2) = 0.0
Precision.round(0.0, 2, BigDecimal.ROUND_UP) = 0.0

Seems the reason is usage of extending float to double inside round functions and getting influence of memory trash as value.

I think, same problem will be found at usage of other round modes.