tensors

src/mol-base/math/_spec/tensor.spec.ts

+/**
+ * Copyright (c) 2017 mol* contributors, licensed under MIT, See LICENSE file for more info.
+ *
+ * @author David Sehnal <david.sehnal@gmail.com>
+ */
+
+import T from '../tensor'
+import { Mat4 } from '../linear-algebra-3d'
+
+describe('tensor', () => {
+    it('vector', () => {
+        const V = T.Vector(3);
+        const data = V.create();
+
+        V.set(data, 0, 1);
+        V.set(data, 1, 2);
+        V.set(data, 2, 3);
+
+        expect(data).toEqual(new Float64Array([1, 2, 3]));
+        expect(V.get(data, 0)).toEqual(1);
+        expect(V.get(data, 1)).toEqual(2);
+        expect(V.get(data, 2)).toEqual(3);
+    });
+
+    it('matrix cm', () => {
+        const M = T.ColumnMajorMatrix(3, 2, Int32Array);
+        const data = M.create()
+
+        // rows: [ [0, 1], [1, 2], [2, 3]  ]
+        for (let i = 0; i < 3; i++) {
+            for (let j = 0; j < 2; j++) {
+                M.set(data, i, j, i + j);
+            }
+        }
+
+        expect(data).toEqual(new Int32Array([0, 1, 2, 1, 2, 3]));
+    });
+
+    it('matrix rm', () => {
+        const M = T.RowMajorMatrix(3, 2, Int32Array);
+        const data = M.create();
+
+        // rows: [ [0, 1], [1, 2], [2, 3]  ]
+        for (let i = 0; i < 3; i++) {
+            for (let j = 0; j < 2; j++) {
+                M.set(data, i, j, i + j);
+            }
+        }
+        expect(data).toEqual(new Int32Array([0, 1, 1, 2, 2, 3]));
+    });
+
+    it('mat4 equiv', () => {
+        const M = T.ColumnMajorMatrix(4, 4);
+        const data = M.create();
+        const m = Mat4.zero();
+
+        for (let i = 0; i < 4; i++) {
+            for (let j = 0; j < 4; j++) {
+                const v = (i + 1) * (j + 2);
+                M.set(data, i, j, v);
+                Mat4.setValue(m, i, j, v);
+            }
+        }
+
+        for (let i = 0; i < 16; i++) expect(data[i]).toEqual(m[i]);
+    });
+
+    it('2d ij', () => {
+        const M = T.Space([3, 4], [0, 1]);
+        const data = M.create();
+        const exp = new Float64Array(3 * 4)
+
+        let o = 0;
+        for (let i = 0; i < 3; i++) {
+            for (let j = 0; j < 4; j++) {
+                M.set(data, i, j, o);
+                exp[o] = o;
+                o++;
+            }
+        }
+
+        expect(data).toEqual(exp);
+    });
+
+    it('2d ji', () => {
+        const M = T.Space([3, 4], [1, 0]);
+        const data = M.create();
+        const exp = new Float64Array(3 * 4)
+
+        let o = 0;
+        for (let j = 0; j < 4; j++) {
+            for (let i = 0; i < 3; i++) {
+                M.set(data, i, j, o);
+                exp[o] = o;
+                o++;
+            }
+        }
+
+        expect(data).toEqual(exp);
+    });
+
+    it('3d ijk', () => {
+        const M = T.Space([3, 4, 5], [0, 1, 2]);
+        const data = M.create();
+        const exp = new Float64Array(3 * 4 * 5)
+
+        let o = 0;
+        for (let i = 0; i < 3; i++) {
+            for (let j = 0; j < 4; j++) {
+                for (let k = 0; k < 5; k++) {
+                    M.set(data, i, j, k, o);
+                    exp[o] = o;
+                    o++;
+                }
+            }
+        }
+
+        expect(data).toEqual(exp);
+    });
+
+    it('3d ikj', () => {
+        const M = T.Space([3, 3, 3], [0, 2, 1]);
+        const data = M.create();
+        const exp = new Float64Array(3 * 3 * 3)
+
+        let o = 0;
+        for (let i = 0; i < 3; i++) {
+            for (let k = 0; k < 3; k++) {
+                for (let j = 0; j < 3; j++) {
+                    M.set(data, i, j, k, o);
+                    exp[o] = o;
+                    o++;
+                }
+            }
+        }
+
+        expect(data).toEqual(exp);
+    });
+
+    it('3d jik', () => {
+        const M = T.Space([3, 3, 3], [1, 0, 2]);
+        const data = M.create();
+        const exp = new Float64Array(3 * 3 * 3)
+
+        let o = 0;
+        for (let j = 0; j < 3; j++) {
+            for (let i = 0; i < 3; i++) {
+                for (let k = 0; k < 3; k++) {
+                    M.set(data, i, j, k, o);
+                    exp[o] = o;
+                    o++;
+                }
+            }
+        }
+
+        expect(data).toEqual(exp);
+    });
+    it('3d jki', () => {
+        const M = T.Space([3, 3, 3], [1, 2, 0]);
+        const data = M.create();
+        const exp = new Float64Array(3 * 3 * 3)
+
+        let o = 0;
+        for (let j = 0; j < 3; j++) {
+            for (let k = 0; k < 3; k++) {
+                for (let i = 0; i < 3; i++) {
+                    M.set(data, i, j, k, o);
+                    exp[o] = o;
+                    o++;
+                }
+            }
+        }
+
+        expect(data).toEqual(exp);
+    });
+
+    it('3d kij', () => {
+        const M = T.Space([3, 3, 3], [2, 0, 1]);
+        const data = M.create();
+        const exp = new Float64Array(3 * 3 * 3)
+
+        let o = 0;
+        for (let k = 0; k < 3; k++) {
+            for (let i = 0; i < 3; i++) {
+                for (let j = 0; j < 3; j++) {
+                    M.set(data, i, j, k, o);
+                    exp[o] = o;
+                    o++;
+                }
+            }
+        }
+
+        expect(data).toEqual(exp);
+    });
+
+    it('3d kji', () => {
+        const M = T.Space([3, 3, 3], [2, 1, 0]);
+        const data = M.create();
+        const exp = new Float64Array(3 * 3 * 3)
+
+        let o = 0;
+        for (let k = 0; k < 3; k++) {
+            for (let j = 0; j < 3; j++) {
+                for (let i = 0; i < 3; i++) {
+                    M.set(data, i, j, k, o);
+                    exp[o] = o;
+                    o++;
+                }
+            }
+        }
+
+        expect(data).toEqual(exp);
+    });
+});
\ No newline at end of file

src/mol-base/math/tensor.ts

+/**
+ * Copyright (c) 2017 mol* contributors, licensed under MIT, See LICENSE file for more info.
+ *
+ * @author David Sehnal <david.sehnal@gmail.com>
+ */
+
+interface Tensor extends Array<number> { '@type': 'tensor' }
+
+namespace Tensor {
+    export type ArrayCtor = { new (size: number): ArrayLike<number> }
+
+    export interface Space {
+        readonly dimensions: ReadonlyArray<number>,
+        readonly axisOrderSlowToFast: ReadonlyArray<number>,
+        create(array?: ArrayCtor): Tensor,
+        get(data: Tensor, ...coords: number[]): number
+        set(data: Tensor, ...coordsAndValue: number[]): number
+    }
+
+    interface Layout {
+        dimensions: number[],
+        // slowest to fastest changing
+        axisOrderSlowToFast: number[],
+        axisOrderFastToSlow: number[],
+        accessDimensions: number[],
+        // if not specified, use Float64Array
+        defaultCtor: ArrayCtor
+    }
+
+    function Layout(dimensions: number[], axisOrderSlowToFast: number[], ctor?: ArrayCtor): Layout {
+        // need to reverse the axis order for better access.
+        const axisOrderFastToSlow: number[] = [];
+        for (let i = 0; i < axisOrderSlowToFast.length; i++) axisOrderFastToSlow[i] = axisOrderSlowToFast[axisOrderSlowToFast.length - i - 1];
+
+        const accessDimensions = [1];
+        for (let i = 1; i < dimensions.length; i++) accessDimensions[i] = dimensions[axisOrderFastToSlow[i - 1]];
+        return { dimensions, axisOrderFastToSlow, axisOrderSlowToFast, accessDimensions, defaultCtor: ctor || Float64Array }
+    }
+
+    export function Space(dimensions: number[], axisOrderSlowToFast: number[], ctor?: ArrayCtor): Space {
+        const layout = Layout(dimensions, axisOrderSlowToFast, ctor);
+        const { get, set } = accessors(layout);
+        return { dimensions: [...dimensions], axisOrderSlowToFast: [...axisOrderSlowToFast], create: creator(layout), get, set };
+    }
+
+    export function Vector(d: number, ctor?: ArrayCtor) { return Space([d], [0], ctor); }
+    export function ColumnMajorMatrix(rows: number, cols: number, ctor?: ArrayCtor) { return Space([rows, cols], [1, 0], ctor); }
+    export function RowMajorMatrix(rows: number, cols: number, ctor?: ArrayCtor) { return Space([rows, cols], [0, 1], ctor); }
+
+    function accessors(layout: Layout): { get: Space['get'], set: Space['set'] } {
+        const { dimensions, axisOrderFastToSlow: ao } = layout;
+        switch (dimensions.length) {
+            case 1: return { get: (t, d) => t[d], set: (t, d, x) => t[d] = x };
+            case 2: {
+                // column major
+                if (ao[0] === 0 && ao[1] === 1) {
+                    const rows = dimensions[0];
+                    return { get: (t, i, j) => t[j * rows + i], set: (t, i, j, x) => t[j * rows + i] = x };
+                }
+                if (ao[0] === 1 && ao[1] === 0) {
+                    const cols = dimensions[1];
+                    return { get: (t, i, j) => t[i * cols + j], set: (t, i, j, x) => t[i * cols + j] = x };
+                }
+                throw new Error('bad axis order')
+            }
+            case 3: {
+                if (ao[0] === 0 && ao[1] === 1 && ao[2] === 2) { // 012 ijk
+                    const u = dimensions[0], v = dimensions[1], uv = u * v;
+                    return { get: (t, i, j, k) => t[i + j * u + k * uv], set: (t, i, j, k, x ) => t[i + j * u + k * uv] = x };
+                }
+                if (ao[0] === 0 && ao[1] === 2 && ao[2] === 1) { // 021 ikj
+                    const u = dimensions[0], v = dimensions[2], uv = u * v;
+                    return { get: (t, i, j, k) => t[i + k * u + j * uv], set: (t, i, j, k, x ) => t[i + k * u + j * uv] = x };
+                }
+                if (ao[0] === 1 && ao[1] === 0 && ao[2] === 2) { // 102 jik
+                    const u = dimensions[1], v = dimensions[0], uv = u * v;
+                    return { get: (t, i, j, k) => t[j + i * u + k * uv], set: (t, i, j, k, x ) => t[j + i * u + k * uv] = x };
+                }
+                if (ao[0] === 1 && ao[1] === 2 && ao[2] === 0) { // 120 jki
+                    const u = dimensions[1], v = dimensions[2], uv = u * v;
+                    return { get: (t, i, j, k) => t[j + k * u + i * uv], set: (t, i, j, k, x ) => t[j + k * u + i * uv] = x };
+                }
+                if (ao[0] === 2 && ao[1] === 0 && ao[2] === 1) { // 201 kij
+                    const u = dimensions[2], v = dimensions[0], uv = u * v;
+                    return { get: (t, i, j, k) => t[k + i * u + j * uv], set: (t, i, j, k, x ) => t[k + i * u + j * uv] = x };
+                }
+                if (ao[0] === 2 && ao[1] === 1 && ao[2] === 0) { // 210 kji
+                    const u = dimensions[2], v = dimensions[1], uv = u * v;
+                    return { get: (t, i, j, k) => t[k + j * u + i * uv], set: (t, i, j, k, x ) => t[k + j * u + i * uv] = x };
+                }
+                throw new Error('bad axis order')
+            }
+            default: return {
+                get: (t, ...c) => t[dataOffset(layout, c)],
+                set: (t, ...c) => t[dataOffset(layout, c)] = c[c.length - 1]
+            };
+        }
+    }
+
+    function creator(layout: Layout): Space['create'] {
+        const { dimensions: ds } = layout;
+        let size = 1;
+        for (let i = 0, _i = ds.length; i < _i; i++) size *= ds[i];
+        return ctor => new (ctor || layout.defaultCtor)(size) as Tensor;
+    }
+
+    function dataOffset(layout: Layout, coord: number[]) {
+        const { accessDimensions: acc, axisOrderFastToSlow: ao } = layout;
+        const d = acc.length - 1;
+        let o = acc[d] * coord[ao[d]];
+        for (let i = d - 1; i >= 0; i--) {
+            o = (o + coord[ao[i]]) * acc[i];
+        }
+        return o;
+    }
+}
+
+export default Tensor
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