How to convert midi note to frequency in C, C++, Python, JS and PHP

midi-note-to-freq.md

JS

function noteToFreq(note) {
    let a = 440; //frequency of A (coomon value is 440Hz)
    return (a / 32) * (2 ** ((note - 9) / 12));
}

PHP

function noteToFreq($note) {
    $a = 440; //frequency of A (coomon value is 440Hz)
    return ($a / 32) * (2 ** (($note - 9) / 12));
}

python 3

def noteToFreq(note):
    a = 440 #frequency of A (coomon value is 440Hz)
    return (a / 32) * (2 ** ((note - 9) / 12))

c / c++

#include <math.h> //<cmath> in case of c++

float noteToFreq(int note) {
    float a = 440; //frequency of A (coomon value is 440Hz)
    return (a / 32) * pow(2, ((note - 9) / 12.0));
}

Hi. We don't have x variable in a C version of noteToFreq, instead we have int note.

#include <math.h> 

float noteToFreq(int note) {
    int a = 440; // frequency of A (coomon value is 440Hz)
    return (a / 32) * pow(2, ((note - 9) / 12));
}

Hi. We don't have x variable in a C version of noteToFreq, instead we have int note.

Sorry about that. Fixed

Thanks!

I believe in c/c++ the type of a / 32 is int. In other words, the floating point part is lost before the result of the expression is multiplied with pow(...).

I believe in c/c++ the type of a / 32 is int. In other words, the floating point part is lost before the result of the expression is multiplied with pow(...).

Yes, that's true. honestly c version was "automatically" generated without even attempt of compiling it.. and that was a mistake.
thanks for you comment should be fixed including second similar error.