feat!: add fromIndex support to blas/ext/base/ndarray/zindex-of-falsy

lib/node_modules/@stdlib/blas/ext/base/ndarray/zindex-of-falsy/README.md

@@ -42,25 +42,38 @@ Returns the index of the first falsy element in a one-dimensional double-precisi
 
 ```javascript
 var Complex128Vector = require( '@stdlib/ndarray/vector/complex128' );
+var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
 
 var x = new Complex128Vector( [ 1.0, 2.0, 0.0, 0.0, 4.0, 5.0 ] );
 
-var idx = zindexOfFalsy( [ x ] );
+var fromIndex = scalar2ndarray( 0, {
+    'dtype': 'generic'
+});
+
+var idx = zindexOfFalsy( [ x, fromIndex ] );
 // returns 1
 ```
 
 The function has the following parameters:
 
--   **arrays**: array-like object containing a one-dimensional input ndarray.
+-   **arrays**: array-like object containing the following ndarrays:
+
+    -   a one-dimensional input ndarray.
+    -   a zero-dimensional ndarray containing the index from which to begin searching.
 
 If the function is unable to find a falsy element, the function returns `-1`.
 
 ```javascript
 var Complex128Vector = require( '@stdlib/ndarray/vector/complex128' );
+var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
 
 var x = new Complex128Vector( [ 1.0, 2.0, 3.0, 4.0 ] );
 
-var idx = zindexOfFalsy( [ x ] );
+var fromIndex = scalar2ndarray( 0, {
+    'dtype': 'generic'
+});
+
+var idx = zindexOfFalsy( [ x, fromIndex ] );
 // returns -1
 ```
 
@@ -74,6 +87,7 @@ var idx = zindexOfFalsy( [ x ] );
 
 -   A complex number is falsy when its real and imaginary components are both falsy.
 -   The function treats `NaN` values as falsy.
+-   If a specified starting search index is negative, the function resolves the starting search index by counting backward from the last element (where `-1` refers to the last element).
 
 </section>
 
@@ -88,6 +102,7 @@ var idx = zindexOfFalsy( [ x ] );
 ```javascript
 var bernoulli = require( '@stdlib/random/array/bernoulli' );
 var Complex128Vector = require( '@stdlib/ndarray/vector/complex128' );
+var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
 var ndarray2array = require( '@stdlib/ndarray/to-array' );
 var zindexOfFalsy = require( '@stdlib/blas/ext/base/ndarray/zindex-of-falsy' );
 
@@ -97,7 +112,11 @@ var buf = bernoulli( 10*2, 0.7, {
 var x = new Complex128Vector( buf.buffer );
 console.log( ndarray2array( x ) );
 
-var idx = zindexOfFalsy( [ x ] );
+var fromIndex = scalar2ndarray( 0, {
+    'dtype': 'generic'
+});
+
+var idx = zindexOfFalsy( [ x, fromIndex ] );
 console.log( idx );
 ```
 

lib/node_modules/@stdlib/blas/ext/base/ndarray/zindex-of-falsy/benchmark/benchmark.js

@@ -24,6 +24,7 @@ var bench = require( '@stdlib/bench' );
 var pow = require( '@stdlib/math/base/special/pow' );
 var isInteger = require( '@stdlib/assert/is-integer' ).isPrimitive;
 var ones = require( '@stdlib/ndarray/ones' );
+var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
 var format = require( '@stdlib/string/format' );
 var pkg = require( './../package.json' ).name;
 var zindexOfFalsy = require( './../lib' );
@@ -46,7 +47,13 @@ var options = {
 * @returns {Function} benchmark function
 */
 function createBenchmark( len ) {
-	var x = ones( [ len ], options );
+	var fromIndex;
+	var x;
+
+	x = ones( [ len ], options );
+	fromIndex = scalar2ndarray( 0, {
+		'dtype': 'generic'
+	});
 	return benchmark;
 
 	/**
@@ -61,7 +68,7 @@ function createBenchmark( len ) {
 
 		b.tic();
 		for ( i = 0; i < b.iterations; i++ ) {
-			out = zindexOfFalsy( [ x ] );
+			out = zindexOfFalsy( [ x, fromIndex ] );
 			if ( out !== out ) {
 				b.fail( 'should return an integer' );
 			}

lib/node_modules/@stdlib/blas/ext/base/ndarray/zindex-of-falsy/docs/repl.txt

@@ -3,17 +3,25 @@
     Returns the index of the first falsy element in a one-dimensional double-
     precision complex floating-point ndarray.
 
-    If unable to find a falsy element, the function returns `-1`.
-
     A complex number is falsy when its real and imaginary components are both
     falsy.
 
     The function treats `NaN` values as falsy.
 
+    If a specified starting search index is negative, the function resolves the
+    starting search index by counting backward from the last element (where `-1`
+    refers to the last element).
+
+    If unable to find a falsy element, the function returns `-1`.
+
     Parameters
     ----------
     arrays: ArrayLikeObject<ndarray>
-        Array-like object containing a one-dimensional input ndarray.
+        Array-like object containing the following ndarrays:
+
+        - a one-dimensional input ndarray.
+        - a zero-dimensional ndarray containing the index from which to begin
+        searching.
 
     Returns
     -------
@@ -23,7 +31,8 @@
     Examples
     --------
     > var x = new {{alias:@stdlib/ndarray/vector/complex128}}( [ 1.0, 2.0, 0.0, 0.0 ] );
-    > {{alias}}( [ x ] )
+    > var i = {{alias:@stdlib/ndarray/from-scalar}}( 0, { 'dtype': 'generic' } );
+    > {{alias}}( [ x, i ] )
     1
 
     See Also

lib/node_modules/@stdlib/blas/ext/base/ndarray/zindex-of-falsy/docs/types/index.d.ts

@@ -20,23 +20,35 @@
 
 /// <reference types="@stdlib/types"/>
 
-import { complex128ndarray } from '@stdlib/types/ndarray';
+import { complex128ndarray, typedndarray } from '@stdlib/types/ndarray';
 
 /**
 * Returns the index of the first falsy element in a one-dimensional double-precision complex floating-point ndarray.
 *
+* ## Notes
+*
+* -   The function expects the following ndarrays:
+*
+*     -   a one-dimensional input ndarray.
+*     -   a zero-dimensional ndarray containing the index from which to begin searching.
+*
 * @param arrays - array-like object containing ndarrays
 * @returns index
 *
 * @example
 * var Complex128Vector = require( '@stdlib/ndarray/vector/complex128' );
+* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
 *
 * var x = new Complex128Vector( [ 1.0, 2.0, 0.0, 0.0, 4.0, 5.0 ] );
 *
-* var idx = zindexOfFalsy( [ x ] );
+* var fromIndex = scalar2ndarray( 0, {
+*     'dtype': 'generic'
+* });
+*
+* var idx = zindexOfFalsy( [ x, fromIndex ] );
 * // returns 1
 */
-declare function zindexOfFalsy( arrays: [ complex128ndarray ] ): number;
+declare function zindexOfFalsy( arrays: [ complex128ndarray, typedndarray<number> ] ): number;
 
 
 // EXPORTS //

lib/node_modules/@stdlib/blas/ext/base/ndarray/zindex-of-falsy/docs/types/test.ts

@@ -19,6 +19,7 @@
 /* eslint-disable space-in-parens */
 
 import zeros = require( '@stdlib/ndarray/zeros' );
+import scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
 import zindexOfFalsy = require( './index' );
 
 
@@ -29,8 +30,11 @@ import zindexOfFalsy = require( './index' );
 	const x = zeros( [ 10 ], {
 		'dtype': 'complex128'
 	});
+	const fromIndex = scalar2ndarray( 0, {
+		'dtype': 'generic'
+	});
 
-	zindexOfFalsy( [ x ] ); // $ExpectType number
+	zindexOfFalsy( [ x, fromIndex ] ); // $ExpectType number
 }
 
 // The compiler throws an error if the function is provided a first argument which is not an array of ndarrays...
@@ -51,7 +55,10 @@ import zindexOfFalsy = require( './index' );
 	const x = zeros( [ 10 ], {
 		'dtype': 'complex128'
 	});
+	const fromIndex = scalar2ndarray( 0, {
+		'dtype': 'generic'
+	});
 
 	zindexOfFalsy(); // $ExpectError
-	zindexOfFalsy( [ x ], {} ); // $ExpectError
+	zindexOfFalsy( [ x, fromIndex ], {} ); // $ExpectError
 }

lib/node_modules/@stdlib/blas/ext/base/ndarray/zindex-of-falsy/examples/index.js

@@ -20,6 +20,7 @@
 
 var bernoulli = require( '@stdlib/random/array/bernoulli' );
 var Complex128Vector = require( '@stdlib/ndarray/vector/complex128' );
+var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
 var ndarray2array = require( '@stdlib/ndarray/to-array' );
 var zindexOfFalsy = require( './../lib' );
 
@@ -29,5 +30,9 @@ var buf = bernoulli( 10*2, 0.7, {
 var x = new Complex128Vector( buf.buffer );
 console.log( ndarray2array( x ) );
 
-var idx = zindexOfFalsy( [ x ] );
+var fromIndex = scalar2ndarray( 0, {
+	'dtype': 'generic'
+});
+
+var idx = zindexOfFalsy( [ x, fromIndex ] );
 console.log( idx );

lib/node_modules/@stdlib/blas/ext/base/ndarray/zindex-of-falsy/lib/index.js

@@ -25,11 +25,16 @@
 *
 * @example
 * var Complex128Vector = require( '@stdlib/ndarray/vector/complex128' );
+* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
 * var zindexOfFalsy = require( '@stdlib/blas/ext/base/ndarray/zindex-of-falsy' );
 *
 * var x = new Complex128Vector( [ 1.0, 2.0, 0.0, 0.0, 4.0, 5.0 ] );
 *
-* var idx = zindexOfFalsy( [ x ] );
+* var fromIndex = scalar2ndarray( 0, {
+*     'dtype': 'generic'
+* });
+*
+* var idx = zindexOfFalsy( [ x, fromIndex ] );
 * // returns 1
 */
 

lib/node_modules/@stdlib/blas/ext/base/ndarray/zindex-of-falsy/lib/main.js

@@ -20,10 +20,12 @@
 
 // MODULES //
 
+var ndarraylike2scalar = require( '@stdlib/ndarray/base/ndarraylike2scalar' );
 var numelDimension = require( '@stdlib/ndarray/base/numel-dimension' );
 var getStride = require( '@stdlib/ndarray/base/stride' );
 var getOffset = require( '@stdlib/ndarray/base/offset' );
 var getData = require( '@stdlib/ndarray/base/data-buffer' );
+var clipIndex = require( '@stdlib/ndarray/base/clip-index' );
 var strided = require( '@stdlib/blas/ext/base/zindex-of-falsy' ).ndarray;
 
 
@@ -37,21 +39,50 @@ var strided = require( '@stdlib/blas/ext/base/zindex-of-falsy' ).ndarray;
 * -   The function expects the following ndarrays:
 *
 *     -   a one-dimensional input ndarray.
+*     -   a zero-dimensional ndarray containing the index from which to begin searching.
 *
 * @param {ArrayLikeObject<Object>} arrays - array-like object containing ndarrays
 * @returns {integer} index
 *
 * @example
 * var Complex128Vector = require( '@stdlib/ndarray/vector/complex128' );
+* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
 *
 * var x = new Complex128Vector( [ 1.0, 2.0, 0.0, 0.0, 4.0, 5.0 ] );
 *
-* var idx = zindexOfFalsy( [ x ] );
+* var fromIndex = scalar2ndarray( 0, {
+*     'dtype': 'generic'
+* });
+*
+* var idx = zindexOfFalsy( [ x, fromIndex ] );
 * // returns 1
 */
 function zindexOfFalsy( arrays ) {
-	var x = arrays[ 0 ];
-	return strided( numelDimension( x, 0 ), getData( x ), getStride( x, 0 ), getOffset( x ) ); // eslint-disable-line max-len
+	var fromIndex;
+	var stride;
+	var offset;
+	var idx;
+	var N;
+	var x;
+
+	x = arrays[ 0 ];
+	fromIndex = ndarraylike2scalar( arrays[ 1 ] );
+
+	N = numelDimension( x, 0 );
+	fromIndex = clipIndex( fromIndex, N );
+	if ( fromIndex >= N ) {
+		return -1;
+	}
+	N -= fromIndex;
+
+	stride = getStride( x, 0 );
+	offset = getOffset( x ) + ( stride*fromIndex );
+
+	idx = strided( N, getData( x ), stride, offset );
+	if ( idx >= 0 ) {
+		idx += fromIndex;
+	}
+	return idx;
 }