how do i approach "h" parameter to zero in derivative?

Question

I have a few problem with my derivative because it shows me an error when I approach Denominator to zero .

func derivativeOf(fn: (Double) -> Double, atX x: Double) -> Double {
    let h -> 0
    return (fn(x + h) - fn(x))/h 
}

i know my syntax sucks but currently it is common in calculus and mathematical Differential.

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score 1 · Answer 1 · answered Feb 15 '21 at 21:33

You can't express "number approaching zero" as let h -> 0 - this is just an invalid syntax in Swift.

There's also no specific operator for "number approaching zero". But depending on what you need, you could for example express "smallest possible positive number", using Double.leastNonzeroMagnitude:

let h = Double.leastNonzeroMagnitude

how do i approach "h" parameter to zero in derivative?

1 Answers1