Usage

`javascript
var dznrm2 = require( '@stdlib/blas-base-dznrm2' );
`

#### dznrm2( N, x, strideX )

Computes the L2-norm of a complex double-precision floating-point vector.

`javascript
var Complex128Array = require( '@stdlib/array-complex128' );

var x = new Complex128Array( [ 0.3, 0.1, 0.5, 0.0, 0.0, 0.5, 0.0, 0.2 ] );

var norm = dznrm2( 4, x, 1 );
// returns ~0.8
`

The function has the following parameters:

- N: number of indexed elements.
- x: input [Complex128Array][@stdlib/array/complex128].
- strideX: index increment for x.

The N and stride parameters determine which elements in the strided array are accessed at runtime. For example, to traverse every other value,

`javascript
var Complex128Array = require( '@stdlib/array-complex128' );

var x = new Complex128Array( [ -2.0, 1.0, 3.0, -5.0, 4.0, 0.0, -1.0, -3.0 ] );

var norm = dznrm2( 2, x, 2 );
// returns ~4.6
`

Note that indexing is relative to the first index. To introduce an offset, use [typed array][mdn-typed-array] views.

`javascript
var Complex128Array = require( '@stdlib/array-complex128' );

// Initial array:
var x0 = new Complex128Array( [ 1.0, -2.0, 3.0, -4.0, 5.0, -6.0 ] );

// Create an offset view:
var x1 = new Complex128Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element

// Compute the L2-norm:
var norm = dznrm2( 2, x1, 1 );
// returns ~9.3
`

#### dznrm2.ndarray( N, x, strideX, offset )

Computes the L2-norm of a complex double-precision floating-point vector using alternative indexing semantics.

`javascript
var Complex128Array = require( '@stdlib/array-complex128' );

var x = new Complex128Array( [ 0.3, 0.1, 0.5, 0.0, 0.0, 0.5, 0.0, 0.2 ] );

var norm = dznrm2.ndarray( 4, x, 1, 0 );
// returns ~0.8
`

The function has the following additional parameters:

- offsetX: starting index.

While [typed array][mdn-typed-array] views mandate a view offset based on the underlying buffer, the offset parameter supports indexing semantics based on a starting index. For example, to start from the second index,

`javascript
var Complex128Array = require( '@stdlib/array-complex128' );

var x = new Complex128Array( [ 1.0, -2.0, 3.0, -4.0, 5.0, -6.0 ] );

var norm = dznrm2.ndarray( 2, x, 1, 1 );
// returns ~9.3
`