Tensor Basics

1/**2 * Example 01: Tensor Basics3 *4 * Learn the fundamentals of creating and manipulating tensors (N-dimensional arrays).5 * Tensors are the core data structure in Deepbox.6 */7 8import { arange, eye, linspace, ones, tensor, zeros } from "deepbox/ndarray";9 10console.log("=== Tensor Basics ===\n");11 12// 1. Creating tensors from JavaScript arrays13const vector = tensor([1, 2, 3, 4, 5]);14console.log("1D Tensor (vector):");15console.log(vector.toString());16console.log(`Shape: [${vector.shape}], Size: ${vector.size}\n`);17 18// 2. Create a 2D tensor (matrix)19const matrix = tensor([20  [1, 2, 3],21  [4, 5, 6],22]);23console.log("2D Tensor (matrix):");24console.log(matrix.toString());25console.log(`Shape: [${matrix.shape}], Size: ${matrix.size}\n`);26 27// 3. Create a 3D tensor (higher dimensional)28const tensor3d = tensor([29  [30    [1, 2],31    [3, 4],32  ],33  [34    [5, 6],35    [7, 8],36  ],37]);38console.log("3D Tensor:");39console.log(`Shape: [${tensor3d.shape}], Size: ${tensor3d.size}\n`);40 41// 4. Special tensor creation functions42const zeroMatrix = zeros([3, 3]);43console.log("3x3 Zero Matrix:");44console.log(`${zeroMatrix.toString()}\n`);45 46const onesMatrix = ones([2, 4]);47console.log("2x4 Ones Matrix:");48console.log(`${onesMatrix.toString()}\n`);49 50// 5. Create identity matrix (diagonal of ones)51const identity = eye(4);52console.log("4x4 Identity Matrix:");53console.log(`${identity.toString()}\n`);54 55// 6. Create a range of values with a step56const range = arange(0, 10, 2); // start, stop (excluded), step57console.log("Range [0, 10) with step 2:");58console.log(`${range.toString()}\n`);59 60// 7. Create linearly spaced values61const linspaced = linspace(0, 1, 5); // start, stop (included), number of points62console.log("5 values linearly spaced between 0 and 1:");63console.log(`${linspaced.toString()}\n`);64 65// 8. Reshape and transpose with tensor methods66const flat = tensor([1, 2, 3, 4, 5, 6]);67const reshaped = flat.reshape([2, 3]); // one dimension may be -1 to infer its size68console.log("Reshaped [6] -> [2, 3]:");69console.log(`${reshaped.toString()}\n`);70 71console.log("Transposed with .T, shape [2, 3] -> [3, 2]:");72console.log(`${reshaped.T.toString()}\n`);73 74// 9. Read single values back as plain numbers75console.log(`Element at row 1, column 2: ${reshaped.at(1, 2)}`);76console.log(`Sum of all elements: ${reshaped.sum().item()}`);77console.log(`Default dtype: ${reshaped.dtype}`);