repl.txt (3634B)
1 2 {{alias}}( N, x, strideX, y, strideY ) 3 Computes the dot product of two single-precision floating-point vectors. 4 5 The `N`, `strideX`, and `strideY` parameters determine which elements in `x` 6 and `y` are accessed at runtime. 7 8 Indexing is relative to the first index. To introduce an offset, use a typed 9 array view. 10 11 If `N <= 0`, the function returns `0.0`. 12 13 Parameters 14 ---------- 15 N: integer 16 Number of indexed elements. 17 18 x: Float32Array 19 First input array. 20 21 strideX: integer 22 Index increment for `x`. 23 24 y: Float32Array 25 Second input array. 26 27 strideY: integer 28 Index increment for `y`. 29 30 Returns 31 ------- 32 dot: float 33 The dot product of `x` and `y`. 34 35 Examples 36 -------- 37 // Standard usage: 38 > var x = new {{alias:@stdlib/array/float32}}( [ 4.0, 2.0, -3.0, 5.0, -1.0 ] ); 39 > var y = new {{alias:@stdlib/array/float32}}( [ 2.0, 6.0, -1.0, -4.0, 8.0 ] ); 40 > var dot = {{alias}}( x.length, x, 1, y, 1 ) 41 -5.0 42 43 // Strides: 44 > x = new {{alias:@stdlib/array/float32}}( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] ); 45 > y = new {{alias:@stdlib/array/float32}}( [ 1.0, 1.0, 1.0, 1.0, 1.0, 1.0 ] ); 46 > var N = {{alias:@stdlib/math/base/special/floor}}( x.length / 2 ); 47 > dot = {{alias}}( N, x, 2, y, -1 ) 48 9.0 49 50 // Using view offsets: 51 > x = new {{alias:@stdlib/array/float32}}( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] ); 52 > y = new {{alias:@stdlib/array/float32}}( [ 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] ); 53 > var x1 = new {{alias:@stdlib/array/float32}}( x.buffer, x.BYTES_PER_ELEMENT*1 ); 54 > var y1 = new {{alias:@stdlib/array/float32}}( y.buffer, y.BYTES_PER_ELEMENT*3 ); 55 > N = {{alias:@stdlib/math/base/special/floor}}( x.length / 2 ); 56 > dot = {{alias}}( N, x1, -2, y1, 1 ) 57 128.0 58 59 {{alias}}.ndarray( N, x, strideX, offsetX, y, strideY, offsetY ) 60 Computes the dot product of two single-precision floating-point vectors 61 using alternative indexing semantics. 62 63 While typed array views mandate a view offset based on the underlying 64 buffer, the `offsetX` and `offsetY` parameters support indexing based on a 65 starting index. 66 67 Parameters 68 ---------- 69 N: integer 70 Number of indexed elements. 71 72 x: Float32Array 73 First input array. 74 75 strideX: integer 76 Index increment for `x`. 77 78 offsetX: integer 79 Starting index for `x`. 80 81 y: Float32Array 82 Second input array. 83 84 strideY: integer 85 Index increment for `y`. 86 87 offsetY: integer 88 Starting index for `y`. 89 90 Returns 91 ------- 92 dot: float 93 The dot product of `x` and `y`. 94 95 Examples 96 -------- 97 // Standard usage: 98 > var x = new {{alias:@stdlib/array/float32}}( [ 4.0, 2.0, -3.0, 5.0, -1.0 ] ); 99 > var y = new {{alias:@stdlib/array/float32}}( [ 2.0, 6.0, -1.0, -4.0, 8.0 ] ); 100 > var dot = {{alias}}.ndarray( x.length, x, 1, 0, y, 1, 0 ) 101 -5.0 102 103 // Strides: 104 > x = new {{alias:@stdlib/array/float32}}( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] ); 105 > y = new {{alias:@stdlib/array/float32}}( [ 1.0, 1.0, 1.0, 1.0, 1.0, 1.0 ] ); 106 > var N = {{alias:@stdlib/math/base/special/floor}}( x.length / 2 ); 107 > dot = {{alias}}.ndarray( N, x, 2, 0, y, 2, 0 ) 108 9.0 109 110 // Using offset indices: 111 > x = new {{alias:@stdlib/array/float32}}( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] ); 112 > y = new {{alias:@stdlib/array/float32}}( [ 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] ); 113 > N = {{alias:@stdlib/math/base/special/floor}}( x.length / 2 ); 114 > dot = {{alias}}.ndarray( N, x, -2, x.length-1, y, 1, 3 ) 115 128.0 116 117 See Also 118 -------- 119