bench: fix value types

Co-authored-by: Athan <kgryte@gmail.com>
Signed-off-by: Athan <kgryte@gmail.com>

Author: kgryte

lib/node_modules/@stdlib/blas/ext/base/sindex-of-row/benchmark/c/benchmark.length.c

@@ -73,10 +73,10 @@ static void print_results( int iterations, float elapsed ) {
 *
 * @return clock time
 */
-static float tic( void ) {
+static double tic( void ) {
 	struct timeval now;
 	gettimeofday( &now, NULL );
-	return (float)now.tv_sec + (float)now.tv_usec/1.0e6;
+	return (double)now.tv_sec + (double)now.tv_usec/1.0e6;
 }
 
 /**
@@ -98,10 +98,10 @@ static float rand_float( void ) {
 */
 static float benchmark1( int iterations, int N ) {
 	uint8_t *workspace;
-	float elapsed;
+	double elapsed;
 	float *A;
 	float *x;
-	float t;
+	double t;
 	int idx;
 	int i;
 	int j;
@@ -144,10 +144,10 @@ static float benchmark1( int iterations, int N ) {
 */
 static float benchmark2( int iterations, int N ) {
 	uint8_t *workspace;
-	float elapsed;
+	double elapsed;
 	float *A;
 	float *x;
-	float t;
+	double t;
 	int idx;
 	int i;
 	int j;
@@ -185,7 +185,7 @@ static float benchmark2( int iterations, int N ) {
 * Main execution sequence.
 */
 int main( void ) {
-	float elapsed;
+	double elapsed;
 	int count;
 	int iter;
 	int len;
@@ -200,7 +200,7 @@ int main( void ) {
 	count = 0;
 	for ( i = MIN; i <= MAX; i++ ) {
 		len = pow( 10, i );
-		N = (int)sqrt( (float)len );
+		N = (int)sqrt( (double)len );
 		iter = ITERATIONS / pow( 10, i-1 );
 		for ( j = 0; j < REPEATS; j++ ) {
 			count += 1;