refactor: reduce code complexity

PR-URL: #2632
Co-authored-by: Athan Reines <kgryte@gmail.com>
Reviewed-by: Athan Reines <kgryte@gmail.com> 
Signed-off-by: Athan Reines <kgryte@gmail.com>

Author: gunjjoshi

lib/node_modules/@stdlib/math/base/special/floorsd/lib/main.js

@@ -64,11 +64,7 @@ function floorsd( x, n, b ) {
 		isnan( x ) ||
 		isnan( n ) ||
 		n < 1 ||
-		isInfinite( n )
-	) {
-		return NaN;
-	}
-	if (
+		isInfinite( n ) ||
 		isnan( b ) ||
 		b <= 0 ||
 		isInfinite( b )

lib/node_modules/@stdlib/math/base/special/floorsd/src/main.c

@@ -40,27 +40,25 @@
 * // returns 0.03125
 */
 double stdlib_base_floorsd( const double x, const int32_t n, const int32_t b ) {
-	int32_t base;
 	double exp;
 	double s;
 	double y;
 
 	if ( stdlib_base_is_nan( x ) || n < 1 || b <= 0 ) {
 		return 0.0 / 0.0; // NaN
 	}
-	base = b;
 	if ( stdlib_base_is_infinite( x ) || x == 0.0 ) {
 		return x;
 	}
-	if ( base == 10 ) {
+	if ( b == 10 ) {
 		exp = stdlib_base_log10( stdlib_base_abs( x ) );
-	} else if ( base == 2 ) {
+	} else if ( b == 2 ) {
 		exp = stdlib_base_float64_exponent( stdlib_base_abs( x ) );
 	} else {
-		exp = stdlib_base_ln( stdlib_base_abs( x ) ) / stdlib_base_ln( base );
+		exp = stdlib_base_ln( stdlib_base_abs( x ) ) / stdlib_base_ln( (double)b );
 	}
 	exp = stdlib_base_floor( exp - n + 1.0 );
-	s = stdlib_base_pow( base, stdlib_base_abs( exp ) );
+	s = stdlib_base_pow( (double)b, stdlib_base_abs( exp ) );
 
 	// Check for overflow:
 	if ( stdlib_base_is_infinite( s ) ) {