in src/toMidi.ts [170:182]
function min3dForAxis0(array: number[][][]): number[][] {
const minArray = array[0].map(v => v.slice());
// np.min axis=0
for (let x = 1; x < array.length; ++x) {
for (let y = 0; y < array[0].length; ++y) {
for (let z = 0; z < array[0][0].length; ++z) {
minArray[y][z] = Math.min(minArray[y][z], array[x][y][z]);
}
}
}
return minArray;
}