@thi.ng/tensors/integrate.js

0D/1D/2D/3D/4D tensors with extensible polymorphic operations and customizable storage

import { ensureShape } from "./errors.js";
import { Tensor1 } from "./tensor.js";
import { sum } from "./sum.js";
const integrate = (out, a, fn = sum) => {
  const { shape, dim } = a;
  const odim = shape[shape.length - 1];
  if (!out) {
    out = new Tensor1(
      a.type,
      a.storage,
      a.storage.alloc(odim),
      [odim],
      [1]
    );
  }
  ensureShape(out, [odim]);
  const {
    data: odata,
    stride: [tx],
    offset: ox
  } = out;
  const select = new Array(dim).fill(-1);
  for (let i = 0; i < odim; i++) {
    select[dim - 1] = i;
    odata[ox + i * tx] = fn(a.pick(select));
  }
  return out;
};
export {
  integrate
};