Convert between a C double and Cocoa's NSDecimalNumber?

Question

I'm converting an algorithm I wrote in Java to Objective-C. In java the BigDecimal class handles base-10 numbers and can take the primitive double as a constructor arg. In Cocoa's NSDecimalNumber class, however, there is no direct way to construct an instance using a primitive double.

Currently I'm using this (smelly) hack:

    [NSDecimalNumber decimalNumberWithString:[NSString stringWithFormat:@"%1.38f", number]];

Is there a better way?

Answer 1

NSNumber, the superclass of NSDecimalNumber, has a +numberWithDouble: method. That's what you want.

Answer 2

You can also use [[NSDecimalNumber alloc] initWithDouble:(double)], it's just not as obvious.

Answer 3

[NSDecimalNumber numberWithDouble:myDouble]