NSDecimalNumber issue with doubleValue method

Originator:dkulemalin
Number:rdar://42374293 Date Originated:07/19/2018
Status:OPEN Resolved:NO
Product:iOS Product Version:11.0
Classification:Other Reproducible:100%
 
Area:
Foundation

Summary:
NSDecimalNumber doubleValue method returns not accurate value.

Steps to Reproduce:

    double a = 7928.46;
    NSDecimalNumber *number = (NSDecimalNumber *)[NSDecimalNumber numberWithDouble:a];
    double b = [number doubleValue];
    BOOL equal = (a - b) == 0;
    double c = [[number stringValue] doubleValue];
    BOOL equal2 = a - c == 0;

Expected Results:
   equal == YES
   equal2 == YES

Actual Results:
   equal == NO (because b == 7928.4600000000009)
   equal2 == YES

Is it possible to improve this method in order to return accurate values when value itself is accurate?

Version/Build:
xCode 9.4.

Comments


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