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objective c - NSExpression 1/2

I want to calculate a string, which I'm doing by this:

NSExpression *expression = [NSExpression expressionWithFormat:calculationString];
float result = [[expression expressionValueWithObject:nil context:nil] floatValue];
NSLog(@"%f", result);

The problem is, when calculationstring is 1/2, the result is 0. I tried to change float with double and NSNumber and the %f to %f and %@, but I always just get 0. What to I have to change?

Also if it matters, I am in Europe, so I have commas instead of points for this value, but it shouldn't matter as I am logging with %f which shows it as points. Just for information

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by (71.8m points)

Basically, you just need to tell it that you are performing floating point operation,

1.0/2
1.0/2.0
1/2.0

Will all work


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