Compute the principal square root of each element in a strided array.
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Compute the principal square root for each element in a strided array.
The principal square root is defined as
\sqrt{x^2} = \begin{matrix} x, & \textrm{if}\ x \geq 0\end{matrix}
npm install @stdlib/math-strided-special-sqrt
Alternatively,
script
tag without installation and bundlers, use the ES Module available on the esm
branch (see README).deno
branch (see README for usage intructions).umd
branch (see README).The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.
To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.
var sqrt = require( '@stdlib/math-strided-special-sqrt' );
Computes the principal square root for each element in a strided array x
and assigns the results to elements in a strided array y
.
var Float64Array = require( '@stdlib/array-float64' );
var x = new Float64Array( [ 0.0, 4.0, 9.0, 12.0, 24.0 ] );
// Perform operation in-place:
sqrt( x.length, 'float64', x, 1, 'float64', x, 1 );
// x => <Float64Array>[ 0.0, 2.0, 3.0, ~3.464, ~4.899 ]
The function accepts the following arguments:
x
.x
.y
.y
.The N
and stride
parameters determine which elements in x
and y
are accessed at runtime. For example, to index every other value in x
and the first N
elements of y
in reverse order,
var Float64Array = require( '@stdlib/array-float64' );
var x = new Float64Array( [ 0.0, 4.0, 9.0, 12.0, 24.0, 64.0 ] );
var y = new Float64Array( [ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ] );
sqrt( 3, 'float64', x, 2, 'float64', y, -1 );
// y => <Float64Array>[ ~4.899, 3.0, 0.0, 0.0, 0.0, 0.0 ]
Note that indexing is relative to the first index. To introduce an offset, use typed array
views.
var Float64Array = require( '@stdlib/array-float64' );
// Initial arrays...
var x0 = new Float64Array( [ 0.0, 4.0, 9.0, 12.0, 24.0, 64.0 ] );
var y0 = new Float64Array( [ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ] );
// Create offset views...
var x1 = new Float64Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
var y1 = new Float64Array( y0.buffer, y0.BYTES_PER_ELEMENT*3 ); // start at 4th element
sqrt( 3, 'float64', x1, -2, 'float64', y1, 1 );
// y0 => <Float64Array>[ 0.0, 0.0, 0.0, 8.0, ~3.464, 2.0 ]
Computes the principal square root for each element in a strided array x
and assigns the results to elements in a strided array y
using alternative indexing semantics.
var Float64Array = require( '@stdlib/array-float64' );
var x = new Float64Array( [ 0.0, 4.0, 9.0, 12.0, 24.0 ] );
var y = new Float64Array( [ 0.0, 0.0, 0.0, 0.0, 0.0 ] );
sqrt.ndarray( x.length, 'float64', x, 1, 0, 'float64', y, 1, 0 );
// y => <Float64Array>[ 0.0, 2.0, 3.0, ~3.464, ~4.899 ]
The function accepts the following additional arguments:
x
.y
.While typed array
views mandate a view offset based on the underlying buffer
, the offsetX
and offsetY
parameters support indexing semantics based on starting indices. For example, to index every other value in x
starting from the second value and to index the last N
elements in y
,
var Float64Array = require( '@stdlib/array-float64' );
var x = new Float64Array( [ 0.0, 4.0, 9.0, 12.0, 24.0, 64.0 ] );
var y = new Float64Array( [ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ] );
sqrt.ndarray( 3, 'float64', x, 2, 1, 'float64', y, -1, y.length-1 );
// y => <Float64Array>[ 0.0, 0.0, 0.0, 8.0, ~3.464, 2.0 ]
var uniform = require( '@stdlib/random-base-uniform' ).factory;
var filledarray = require( '@stdlib/array-filled' );
var filledarrayBy = require( '@stdlib/array-filled-by' );
var dtypes = require( '@stdlib/array-typed-real-float-dtypes' );
var sqrt = require( '@stdlib/math-strided-special-sqrt' );
var dt;
var x;
var y;
var i;
dt = dtypes();
for ( i = 0; i < dt.length; i++ ) {
x = filledarrayBy( 10, dt[ i ], uniform( 0.0, 100.0 ) );
console.log( x );
y = filledarray( 0.0, x.length, 'generic' );
console.log( y );
sqrt.ndarray( x.length, dt[ i ], x, 1, 0, 'generic', y, -1, y.length-1 );
console.log( y );
console.log( '' );
}
@stdlib/math-strided/special/cbrt
: compute the cube root of each element in a strided array.
@stdlib/math-strided/special/dsqrt
: compute the principal square root for each element in a double-precision floating-point strided array.
@stdlib/math-strided/special/rsqrt
: compute the reciprocal square root for each element in a strided array.
@stdlib/math-strided/special/ssqrt
: compute the principal square root for each element in a single-precision floating-point strided array.
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