Utilities

// creating a vector object let va = new Vector2(1,2); // you can also use the shorthand `V2` let vb = V2(1,2); // you can create a unit vector with a given angle using `Vdir` let vc = Vdir(Math.PI/2); // the same as `V2(0,1)`

let va = V2(1,2); let vb = V2(3,4); let vc, x; // addition vc = va.add(vb); // V2(4,6); // subtraction vc = va.sub(vb); // V2(-2,-2); // scaling vc = va.scale(2); // V2(2,4); // multiplication vc = va.mul(vb); // V2(3,8); // rotation from the origin vc = va.rotate(Math.PI/2); // V2(-2,1); // dot product x = va.dot(vb); // 1*3 + 2*4 = 11; // cross product // * the cross product in 2D is a scalar x = va.cross(vb); // 1*4 - 2*3 = -2; // length x = va.length(); // sqrt(1*1 + 2*2) = sqrt(5); // length squared x = va.length_sq(); // 1*1 + 2*2 = 5; // angle from the positive x-axis x = va.angle(); // atan2(2,1) = 1.1071487177940904; // normalization vc = va.normalize(); // V2(1/sqrt(5), 2/sqrt(5)); // checking for equality x = va.equals(vb); // false; // apply a function let f = (v) => v.add(V2(1,1)); vc = va.apply(f); // V2(2,3); // the same as `vc = f(va)`

// helper function to convert from degrees to radians let angle = to_radian(30); // 0.5235987755982988 let ang2 = to_radian(90); // 1.5707963267948966 = Math.PI/2

// helper function to convert from radians to degrees let angle = to_degree(Math.PI/2); // 90 let ang2 = to_degree(Math.PI/6); // 30

// repeat an array until the length is `len` let arr = [1,2,3]; let new_arr = array_repeat(arr, 5); // [1,2,3,1,2]

// create an equivalently spaced array of numbers from start to end (inclusive) // [start, end] let arr1 = linspace(0, 1, 5); // [0, 0.25, 0.5, 0.75, 1] let arr2 = linspace(0, 1, 4); // [0, 0.333, 0.666, 1]

// create an equivalently spaced array of numbers from start to end (exclusice) // [start, end) let arr1 = linspace_exc(0, 1, 5); // [ 0, 0.2, 0.4, 0.6, 0.8 ] let arr2 = linspace_exc(0, 1, 4); // [ 0, 0.25, 0.5, 0.75 ]

// create an equivalently spaced array of numbers from start to end (exclusive) // [start, end) let arr1 = range(0, 5); // [0, 1, 2, 3, 4] let arr2 = range(0, 5, 1); // [0, 1, 2, 3, 4] let arr3 = range(0, 5, 2); // [0, 2, 4] let arr4 = range(0, 5, 0.5); // [0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5]

// create an equivalently spaced array of numbers from start to end (inclusive) // [start, end] let arr1 = range_inc(0, 5); // [0, 1, 2, 3, 4, 5] let arr2 = range_inc(0, 5, 1); // [0, 1, 2, 3, 4, 5] let arr3 = range_inc(0, 5, 2); // [0, 2, 4] let arr4 = range_inc(0, 5, 0.5); // [0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5]