[system-a] extract gradient-descent/

Author: xieyuheng

TODO.md

@@ -2,9 +2,10 @@
 
 [system-a] `Representation` -- `{ inflate, deflate, update }`
 
-- naked representation
-- lonely representation
+- with `velocityAccumulationFactor`
 
+[system-a] `nakedRepresentation`
+[system-a] `lonelyRepresentation`
 [system-a] `velocityRepresentation` as an instance of `Representation`
 
 # the-book

src/system-a/Scalar.ts

@@ -2,7 +2,7 @@ import {
   gradientStateGetWithDefault,
   gradientStateSet,
   type GradientState,
-} from "./index.js"
+} from "./gradient-descent/index.js"
 
 export type Dual = { "@type": "Dual"; real: number; link: Link }
 
@@ -26,6 +26,12 @@ export function isScalar(x: any): x is Scalar {
   return typeof x === "number" || isDual(x)
 }
 
+export function assertScalar(t: any): asserts t is Scalar {
+  if (!isScalar(t)) {
+    throw new Error(`[assertScalar] ${t}`)
+  }
+}
+
 export function scalarReal(x: Scalar): number {
   if (isDual(x)) {
     return x.real

src/system-a/Tensor.ts

@@ -1,4 +1,4 @@
-import { isScalar, scalarReal, type Scalar } from "./index.js"
+import { isScalar, scalarReal, type Scalar } from "./Scalar.js"
 import { sub } from "./toys/index.js"
 
 export type Tensor = Scalar | Array<Tensor>
@@ -21,18 +21,6 @@ export function rank(t: Tensor): number {
   return shape(t).length
 }
 
-export function assertScalar(t: Tensor): asserts t is Scalar {
-  if (!isScalar(t)) {
-    throw new Error(`[assertScalar] ${t}`)
-  }
-}
-
-export function assertNotScalar(t: Tensor): asserts t is Array<Tensor> {
-  if (isScalar(t)) {
-    throw new Error(`[assertNotScalar] ${t}`)
-  }
-}
-
 export function assertTensor1(t: Tensor): asserts t is Array<Scalar> {
   if (rank(t) !== 1) {
     throw new Error(`[assertTensor1] ${t}`)

src/system-a/GradientState.ts renamed to src/system-a/gradient-descent/GradientState.ts

@@ -1,4 +1,4 @@
-import { type Scalar } from "./index.js"
+import { type Scalar } from "../Scalar.js"
 
 export type GradientState = Map<Scalar, number>
 

src/system-a/gradient.test.ts renamed to src/system-a/gradient-descent/gradient.test.ts

@@ -1,7 +1,7 @@
 import assert from "node:assert"
 import { test } from "node:test"
-import { gradient } from "./index.js"
-import { add, mul, sum } from "./toys/index.js"
+import { add, mul, sum } from "../toys/index.js"
+import { gradient } from "./gradient.js"
 
 test("gradient -- add", () => {
   assert.deepStrictEqual(gradient(add, [1, 1]), [1, 1])

src/system-a/gradient.ts renamed to src/system-a/gradient-descent/gradient.ts

@@ -1,14 +1,10 @@
+import { isScalar, scalarLink, scalarTruncate, type Scalar } from "../Scalar.js"
+import { tensorMap, type Tensor } from "../Tensor.js"
 import {
   emptyGradientState,
   gradientStateGetWithDefault,
-  isScalar,
-  scalarLink,
-  scalarTruncate,
-  tensorMap,
   type GradientState,
-  type Scalar,
-  type Tensor,
-} from "./index.js"
+} from "./GradientState.js"
 
 // The effect of `gradient` on a `DifferentiableFn`
 // is `sum` of all elements of it's result tensor.

src/system-a/gradientDescent.test.ts renamed to src/system-a/gradient-descent/gradientDescent.test.ts

@@ -1,12 +1,8 @@
-import { zip } from "../utils/zip.js"
-import {
-  assertTensorArray,
-  gradient,
-  tensorReal,
-  type Scalar,
-  type Tensor,
-} from "./index.js"
-import { mul, sub } from "./toys/index.js"
+import { zip } from "../../utils/zip.js"
+import type { Scalar } from "../Scalar.js"
+import { assertTensorArray, tensorReal, type Tensor } from "../Tensor.js"
+import { mul, sub } from "../toys/index.js"
+import { gradient } from "./index.js"
 
 export function gradientDescent(
   objective: (...ps: Array<Tensor>) => Scalar,

src/system-a/gradientDescent.ts renamed to src/system-a/gradient-descent/gradientDescent.ts

@@ -1,4 +1,3 @@
 export * from "./GradientState.js"
-export * from "./Scalar.js"
-export * from "./Tensor.js"
 export * from "./gradient.js"
+export * from "./gradientDescent.js"

src/system-a/index.ts renamed to src/system-a/gradient-descent/index.ts

@@ -1,4 +1,5 @@
-import { assertScalar, type Scalar, type Tensor } from "./index.js"
+import { assertScalar, type Scalar } from "./Scalar.js"
+import { type Tensor } from "./Tensor.js"
 import { square, sub, sum } from "./toys/index.js"
 
 export type Target = (xs: Tensor) => (...ps: Array<Tensor>) => Tensor

src/system-a/loss.ts

@@ -1,7 +1,7 @@
 import assert from "assert"
 import { test } from "node:test"
 import { assertTensorAlmostEqual, tensorReal } from "../Tensor.js"
-import { gradientDescent } from "../gradientDescent.js"
+import { gradientDescent } from "../gradient-descent/index.js"
 import { l2Loss } from "../loss.js"
 import { samplingObjective } from "../samplingObjective.js"
 import { line } from "./line.js"

src/system-a/targets/line.test.ts

@@ -1,4 +1,4 @@
-import { type Tensor } from "../index.js"
+import { type Tensor } from "../Tensor.js"
 import { add, mul } from "../toys/index.js"
 
 export function line(x: Tensor): (...ps: [Tensor, Tensor]) => Tensor {

src/system-a/targets/line.ts

@@ -1,7 +1,7 @@
 import assert from "node:assert"
 import { test } from "node:test"
 import { assertTensorAlmostEqual, tensorReal } from "../Tensor.js"
-import { gradientDescent } from "../gradientDescent.js"
+import { gradientDescent } from "../gradient-descent/index.js"
 import { l2Loss } from "../loss.js"
 import { samplingObjective } from "../samplingObjective.js"
 import { plane } from "./plane.js"

src/system-a/targets/plane.test.ts

@@ -1,4 +1,4 @@
-import { type Tensor } from "../index.js"
+import { type Tensor } from "../Tensor.js"
 import { dot } from "../toys/dot.js"
 import { add } from "../toys/index.js"
 

src/system-a/targets/plane.ts

@@ -1,7 +1,7 @@
 import assert from "node:assert"
 import { test } from "node:test"
 import { assertTensorAlmostEqual, tensorReal } from "../Tensor.js"
-import { gradientDescent } from "../gradientDescent.js"
+import { gradientDescent } from "../gradient-descent/index.js"
 import { l2Loss } from "../loss.js"
 import { samplingObjective } from "../samplingObjective.js"
 import { quad } from "./quad.js"

src/system-a/targets/quad.test.ts

@@ -1,4 +1,4 @@
-import { type Tensor } from "../index.js"
+import { type Tensor } from "../Tensor.js"
 import { add, mul, square } from "../toys/index.js"
 
 export function quad(x: Tensor): (...ps: [Tensor, Tensor, Tensor]) => Tensor {

src/system-a/targets/quad.ts

@@ -1,4 +1,4 @@
-import { scalarReal, type Scalar } from "../index.js"
+import { scalarReal, type Scalar } from "../Scalar.js"
 
 export function comparator(
   p: (x: number, y: number) => boolean,

src/system-a/toys/comparator.ts

@@ -1,4 +1,4 @@
-import { type Tensor } from "../index.js"
+import { type Tensor } from "../Tensor.js"
 import { mul, sum } from "./index.js"
 
 export function dot(w: Tensor, x: Tensor): Tensor {

src/system-a/toys/dot.ts

@@ -1,23 +1,18 @@
 import { zip } from "../../utils/zip.js"
-import {
-  assertNotScalar,
-  isScalar,
-  rank,
-  type Scalar,
-  type Tensor,
-} from "../index.js"
+import { isScalar, type Scalar } from "../Scalar.js"
+import { assertTensorArray, rank, type Tensor } from "../Tensor.js"
 
 export function extend2(
   fn: (x: Scalar, y: Scalar) => Scalar,
 ): (x: Tensor, y: Tensor) => Tensor {
   return function extendedFn(x: Tensor, y: Tensor): Tensor {
     if (rank(x) > rank(y)) {
-      assertNotScalar(x)
+      assertTensorArray(x)
       return x.map((x) => extendedFn(x, y))
     }
 
     if (rank(x) < rank(y)) {
-      assertNotScalar(y)
+      assertTensorArray(y)
       return y.map((y) => extendedFn(x, y))
     }
 
@@ -29,8 +24,8 @@ export function extend2(
       return fn(x, y)
     }
 
-    assertNotScalar(x)
-    assertNotScalar(y)
+    assertTensorArray(x)
+    assertTensorArray(y)
 
     return zip(x, y).map(([x, y]) => extendedFnSameShape(x, y))
   }

src/system-a/toys/extend.ts

@@ -1,4 +1,4 @@
-import { Dual, scalarLink, scalarReal, type Scalar } from "../index.js"
+import { Dual, scalarLink, scalarReal, type Scalar } from "../Scalar.js"
 
 export function prim1(
   realFn: (ra: number) => number,

src/system-a/toys/prim.ts

@@ -1,18 +1,18 @@
+import type { Scalar } from "../Scalar.js"
 import {
-  assertNotScalar,
   assertTensor1,
+  assertTensorArray,
   rank,
-  type Scalar,
   type Tensor,
-} from "../index.js"
+} from "../Tensor.js"
 import { addScalar } from "./index.js"
 
 export function sum1(xs: Array<Scalar>): Scalar {
   return xs.reduce((x, result) => addScalar(x, result), 0)
 }
 
 export function sum(x: Tensor): Tensor {
-  assertNotScalar(x)
+  assertTensorArray(x)
   if (rank(x) === 1) {
     assertTensor1(x)
     return sum1(x)

src/system-a/toys/sum.ts

@@ -1,4 +1,4 @@
-import { Dual, scalarLink, scalarReal, type Scalar } from "../index.js"
+import { Dual, scalarLink, scalarReal, type Scalar } from "../Scalar.js"
 
 function addScalar(da: Scalar, db: Scalar): Scalar {
   return Dual(scalarReal(da) + scalarReal(db), (_d, z, state) => {