feat: add C ndarray API and refactor blas/ext/base/dnannsumkbn2

lib/node_modules/@stdlib/blas/ext/base/dnannsumkbn2/README.md

@@ -106,7 +106,7 @@ The function has the following additional parameters:
 -   **offsetX**: starting index for `x`.
 -   **offsetOut**: starting index for `out`.
 
-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 calculate the sum of every other value in `x` starting from the second value
+While [`typed array`][mdn-typed-array] views mandate a view offset based on the underlying buffer, offset parameters support indexing semantics based on starting indices. For example, to calculate the sum of every other value in `x` starting from the second value
 
 ```javascript
 var Float64Array = require( '@stdlib/array/float64' );
@@ -164,8 +164,132 @@ console.log( out );
 
 <!-- /.examples -->
 
+<!-- C interface documentation. -->
+
 * * *
 
+<section class="c">
+
+## C APIs
+
+<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
+
+<section class="intro">
+
+</section>
+
+<!-- /.intro -->
+
+<!-- C usage documentation. -->
+
+<section class="usage">
+
+### Usage
+
+```c
+#include "stdlib/blas/ext/base/dnannsumkbn2.h"
+```
+
+#### stdlib_strided_dnannsumkbn2( N, \*X, strideX, \*n )
+
+Computes the sum of double-precision floating-point strided array elements, ignoring `NaN` values and using a second-order iterative Kahan–Babuška algorithm.
+
+```c
+const double x[] = { 1.0, 2.0, 0.0/0.0, 4.0 };
+CBLAS_INT n = 0;
+
+double v = stdlib_strided_dnannsumkbn2( 4, x, 1, &n );
+// returns 7.0
+```
+
+The function accepts the following arguments:
+
+-   **N**: `[in] CBLAS_INT` number of indexed elements.
+-   **X**: `[in] double*` input array.
+-   **strideX**: `[in] CBLAS_INT` index increment for `X`.
+-   **n**: `[out] CBLAS_INT*` number of non-NaN elements.
+
+```c
+double stdlib_strided_dnannsumkbn2( const CBLAS_INT N, const double *X, const CBLAS_INT strideX, CBLAS_INT *n );
+```
+
+#### stdlib_strided_dnannsumkbn2_ndarray( N, \*X, strideX, offsetX, \*n )
+
+Computes the sum of double-precision floating-point strided array elements, ignoring `NaN` values and using a second-order iterative Kahan–Babuška algorithm and alternative indexing semantics.
+
+```c
+const double x[] = { 1.0, 2.0, 0.0/0.0, 4.0 };
+CBLAS_INT n = 0; 
+
+double v = stdlib_strided_dnannsumkbn2_ndarray( 4, x, 1, 0, &n );
+// returns 7.0
+```
+
+The function accepts the following arguments:
+
+-   **N**: `[in] CBLAS_INT` number of indexed elements.
+-   **X**: `[in] double*` input array.
+-   **strideX**: `[in] CBLAS_INT` index increment for `X`.
+-   **offsetX**: `[in] CBLAS_INT` starting index for `X`.
+-   **n**: `[out] CBLAS_INT*` number of non-NaN elements.
+
+```c
+double stdlib_strided_dnannsumkbn2_ndarray( const CBLAS_INT N, const double *X, const CBLAS_INT strideX, const CBLAS_INT offsetX, CBLAS_INT *n );
+```
+
+</section>
+
+<!-- /.usage -->
+
+<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="notes">
+
+</section>
+
+<!-- /.notes -->
+
+<!-- C API usage examples. -->
+
+<section class="examples">
+
+### Examples
+
+```c
+#include "stdlib/blas/ext/base/dnannsumkbn2.h"
+#include "stdlib/blase/base/shared.h"
+#include <stdio.h>
+
+int main( void ) {
+    // Create a strided array:
+    const double x[] = { 1.0, 2.0, -3.0, -4.0, 5.0, -6.0, -7.0, 8.0, 0.0/0.0, 0.0/0.0 };
+
+    // Specify the number of elements:
+    const int N = 5;
+
+    // Specify the stride length:
+    const int strideX = 2;
+
+    // Initialize a variable for storing the number of non-NaN elements:
+    CBLAS_INT n = 0;
+
+    // Compute the sum:
+    double v = stdlib_strided_dnannsumkbn2( N, x, strideX, &n );
+
+    // Print the result:
+    printf( "sum: %lf\n", v );
+    printf( "n: %"CBLAS_IFMT"\n", n );
+}
+```
+
+</section>
+
+<!-- /.examples -->
+
+</section>
+
+<!-- /.c -->
+
 <section class="references">
 
 ## References

lib/node_modules/@stdlib/blas/ext/base/dnannsumkbn2/benchmark/c/benchmark.length.c

@@ -17,6 +17,7 @@
 */
 
 #include "stdlib/blas/ext/base/dnannsumkbn2.h"
+#include "stdlib/blas/base/shared.h"
 #include <stdlib.h>
 #include <stdio.h>
 #include <math.h>
@@ -94,10 +95,10 @@ static double rand_double( void ) {
 * @param len          array length
 * @return elapsed time in seconds
 */
-static double benchmark( int iterations, int len ) {
+static double benchmark1( int iterations, int len ) {
 	double elapsed;
 	double x[ len ];
-	int64_t n;
+	CBLAS_INT n;
 	double v;
 	double t;
 	int i;
@@ -126,6 +127,45 @@ static double benchmark( int iterations, int len ) {
 	return elapsed;
 }
 
+/**
+* Runs a benchmark.
+*
+* @param iterations   number of iterations
+* @param len          array length
+* @return elapsed time in seconds
+*/
+static double benchmark2( int iterations, int len ) {
+	double elapsed;
+	double x[ len ];
+	CBLAS_INT n;
+	double v;
+	double t;
+	int i;
+
+	for ( i = 0; i < len; i++ ) {
+		if ( rand_double() < 0.2 ) {
+			x[ i ] = 0.0 / 0.0; // NaN
+		} else {
+			x[ i ] = ( rand_double() * 20000.0 ) - 10000.0;
+		}
+	}
+	v = 0.0;
+	n = 0;
+	t = tic();
+	for ( i = 0; i < iterations; i++ ) {
+		v = stdlib_strided_dnannsumkbn2_ndarray( len, x, 1, 0, &n );
+		if ( v != v || n < 0  ) {
+			printf( "should not return NaN\n" );
+			break;
+		}
+	}
+	elapsed = tic() - t;
+	if ( v != v || n < 0 ) {
+		printf( "should not return NaN\n" );
+	}
+	return elapsed;
+}
+
 /**
 * Main execution sequence.
 */
@@ -148,7 +188,18 @@ int main( void ) {
 		for ( j = 0; j < REPEATS; j++ ) {
 			count += 1;
 			printf( "# c::%s:len=%d\n", NAME, len );
-			elapsed = benchmark( iter, len );
+			elapsed = benchmark1( iter, len );
+			print_results( iter, elapsed );
+			printf( "ok %d benchmark finished\n", count );
+		}
+	}
+	for ( i = MIN; i <= MAX; i++ ) {
+		len = pow( 10, i );
+		iter = ITERATIONS / pow( 10, i-1 );
+		for ( j = 0; j < REPEATS; j++ ) {
+			count += 1;
+			printf( "# c::%s:ndarray:len=%d\n", NAME, len );
+			elapsed = benchmark2( iter, len );
 			print_results( iter, elapsed );
 			printf( "ok %d benchmark finished\n", count );
 		}

lib/node_modules/@stdlib/blas/ext/base/dnannsumkbn2/docs/repl.txt

@@ -63,8 +63,8 @@
     algorithm and alternative indexing semantics.
 
     While typed array views mandate a view offset based on the underlying
-    buffer, the offset parameters supports indexing semantics
-    based on a starting index.
+    buffer, offset parameters support indexing semantics based on starting
+    indices.
 
     Parameters
     ----------

lib/node_modules/@stdlib/blas/ext/base/dnannsumkbn2/examples/c/example.c

@@ -17,27 +17,26 @@
 */
 
 #include "stdlib/blas/ext/base/dnannsumkbn2.h"
-#include <stdint.h>
+#include "stdlib/blas/base/shared.h"
 #include <stdio.h>
-#include <inttypes.h>
 
 int main( void ) {
 	// Create a strided array:
 	const double x[] = { 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 0.0/0.0, 0.0/0.0 };
 
 	// Specify the number of elements:
-	const int64_t N = 5;
+	const int N = 5;
 
 	// Specify the stride length:
-	const int64_t stride = 2;
+	const int strideX = 2;
 
 	// Initialize a variable for storing the number of non-NaN elements:
-	int64_t n = 0;
+	CBLAS_INT n = 0;
 
 	// Compute the sum:
-	double v = stdlib_strided_dnannsumkbn2( N, x, stride, &n );
+	double v = stdlib_strided_dnannsumkbn2( N, x, strideX, &n );
 
 	// Print the result:
 	printf( "sum: %lf\n", v );
-	printf( "n: %"PRId64"\n", n );
+	printf( "n: %"CBLAS_IFMT"\n", n );
 }

lib/node_modules/@stdlib/blas/ext/base/dnannsumkbn2/include/stdlib/blas/ext/base/dnannsumkbn2.h

@@ -19,7 +19,7 @@
 #ifndef STDLIB_BLAS_EXT_BASE_DNANNSUMKBN2_H
 #define STDLIB_BLAS_EXT_BASE_DNANNSUMKBN2_H
 
-#include <stdint.h>
+#include "stdlib/blas/base/shared.h"
 
 /*
 * If C++, prevent name mangling so that the compiler emits a binary file having undecorated names, thus mirroring the behavior of a C compiler.
@@ -31,7 +31,12 @@ extern "C" {
 /**
 * Computes the sum of double-precision floating-point strided array elements, ignoring `NaN` values and using a second-order iterative Kahan–Babuška algorithm.
 */
-double stdlib_strided_dnannsumkbn2( const int64_t N, const double *X, const int64_t stride, int64_t *n );
+double API_SUFFIX(stdlib_strided_dnannsumkbn2)( const CBLAS_INT N, const double *X, const CBLAS_INT strideX, CBLAS_INT *n );
+
+/**
+* Computes the sum of double-precision floating-point strided array elements, ignoring `NaN` values and using a second-order iterative Kahan–Babuška algorithm and alternative indexing semantics.
+*/
+double API_SUFFIX(stdlib_strided_dnannsumkbn2_ndarray)( const CBLAS_INT N, const double *X, const CBLAS_INT strideX, const CBLAS_INT offsetX, CBLAS_INT *n );
 
 #ifdef __cplusplus
 }

lib/node_modules/@stdlib/blas/ext/base/dnannsumkbn2/lib/dnannsumkbn2.js

@@ -20,8 +20,8 @@
 
 // MODULES //
 
-var isnan = require( '@stdlib/math/base/assert/is-nan' );
-var abs = require( '@stdlib/math/base/special/abs' );
+var stride2offset = require( '@stdlib/strided/base/stride2offset' );
+var ndarray = require( './ndarray.js' );
 
 
 // MAIN //
@@ -54,72 +54,16 @@ var abs = require( '@stdlib/math/base/special/abs' );
 * // returns <Float64Array>[ 1.0, 3 ]
 */
 function dnannsumkbn2( N, x, strideX, out, strideOut ) {
-	var sum;
-	var ccs;
-	var cs;
-	var cc;
 	var ix;
 	var io;
-	var v;
-	var t;
-	var c;
-	var n;
-	var i;
 
-	if ( strideX < 0 ) {
-		ix = (1-N) * strideX;
-	} else {
-		ix = 0;
-	}
+	ix = stride2offset( N, strideX );
 	if ( strideOut < 0 ) {
 		io = -strideOut;
 	} else {
 		io = 0;
 	}
-	sum = 0.0;
-	if ( N <= 0 ) {
-		out[ io ] = sum;
-		out[ io+strideOut ] = 0;
-		return out;
-	}
-	if ( N === 1 || strideX === 0 ) {
-		if ( isnan( x[ ix ] ) ) {
-			out[ io ] = sum;
-			out[ io+strideOut ] = 0;
-			return out;
-		}
-		out[ io ] = x[ ix ];
-		out[ io+strideOut ] = 1;
-		return out;
-	}
-	ccs = 0.0; // second order correction term for lost low order bits
-	cs = 0.0; // first order correction term for lost low order bits
-	n = 0;
-	for ( i = 0; i < N; i++ ) {
-		v = x[ ix ];
-		if ( isnan( v ) === false ) {
-			t = sum + v;
-			if ( abs( sum ) >= abs( v ) ) {
-				c = (sum-t) + v;
-			} else {
-				c = (v-t) + sum;
-			}
-			sum = t;
-			t = cs + c;
-			if ( abs( cs ) >= abs( c ) ) {
-				cc = (cs-t) + c;
-			} else {
-				cc = (c-t) + cs;
-			}
-			cs = t;
-			ccs += cc;
-			n += 1;
-		}
-		ix += strideX;
-	}
-	out[ io ] = sum + cs + ccs;
-	out[ io+strideOut ] = n;
-	return out;
+	return ndarray( N, x, strideX, ix, out, strideOut, io );
 }