Add math.multinomial and math.oneHot

[dsmilkov]

This change is 

[nsthorat]

This is a great CL! Nice work with the math CPU / GPU testing, this is so much better.

All minor comments below, but I stamped it!

---

Reviewed 9 of 9 files at r1.
Review status: all files reviewed at latest revision, 7 unresolved discussions.

---

package.json, line 16 at r1 (raw file):

    "@types/jasmine": "~2.5.53",
    "@types/polymer": "~1.1.31",
    "@types/seedrandom": "^2.4.27",

use a tilde for consistency?

---

src/math/math.ts, line 1612 at r1 (raw file):

   *     match the location.
   */
  oneHot(indices: Array1D, depth: number, onValue?: number, offValue?: number):

why not just put the default here? onValue = 1, offValue = 0

---

src/math/math_cpu.ts, line 1022 at r1 (raw file):

      indices: Array1D, depth: number, onValue: number,
      offValue: number): Array2D {
    const res = new Float32Array(indices.size * depth);

you need to fill this with offValue

---

src/math/math_cpu.ts, line 1025 at r1 (raw file):

    for (let event = 0; event < indices.size; ++event) {
      res[event * depth + indices.get(event)] = 1;

s/1/onValue

---

src/math/multinomial_test.ts, line 33 at r1 (raw file):

  afterEach(() => {
    math.endScope(null);
  });

Here, and in the other file, can you add an afterAll and dispose the math so we don't create too many webgl rendering contexts?

This will be copy pasted all over the place so best to do it right now.

---

src/math/onehot_test.ts, line 63 at r1 (raw file):

    expect(res.shape).toEqual([4, 3]);
    test_util.expectArraysClose(res.getValues(), expected);
  });

add unit tests for non-0 and 1 on/off values

---

src/math/webgl/multinomial_gpu.ts, line 37 at r1 (raw file):

      uniform float seed;

      const vec2 K1 = vec2(

can you move this out to shader_compiler just like you did for round?

---

Comments from Reviewable

[dsmilkov]

Review status: 2 of 9 files reviewed at latest revision, 7 unresolved discussions, some commit checks pending.

---

package.json, line 16 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

use a tilde for consistency?

nice catch. done

---

src/math/math.ts, line 1612 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

why not just put the default here? onValue = 1, offValue = 0

ah, you're right. didn't occur to me for some reason. done

---

src/math/math_cpu.ts, line 1022 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

you need to fill this with offValue

nice catch. done

---

src/math/math_cpu.ts, line 1025 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

s/1/onValue

ups. rushed this. done. will add tests.

---

src/math/multinomial_test.ts, line 33 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

Here, and in the other file, can you add an afterAll and dispose the math so we don't create too many webgl rendering contexts?

This will be copy pasted all over the place so best to do it right now.

nice. dispose() was missing in the common NDArrayMath class, but added now. The NDArrayMathGPU overwrites it to dispose the webgl resources.

---

src/math/onehot_test.ts, line 63 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

add unit tests for non-0 and 1 on/off values

Done.

---

src/math/webgl/multinomial_gpu.ts, line 37 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

can you move this out to shader_compiler just like you did for round?

Done.

---

Comments from Reviewable