chore: apply suggestions from code review

Signed-off-by: Philipp Burckhardt <[email protected]>

Author: Planeshifter

lib/node_modules/@stdlib/stats/base/dists/cosine/stdev/README.md

@@ -166,8 +166,8 @@ double out = stdlib_base_dists_cosine_stdev( 0.0, 1.0 );
 
 The function accepts the following arguments:
 
--   **mu**: `[in] int` location parameter
--   **s**: `[in] int` scale parameter
+-   **mu**: `[in] int` location parameter.
+-   **s**: `[in] int` scale parameter.
 
 ```c
 double stdlib_base_dists_cosine_stdev( const double mu, const double s );

lib/node_modules/@stdlib/stats/base/dists/cosine/stdev/src/main.c

@@ -22,7 +22,7 @@
 #include "stdlib/constants/float64/pi_squared.h"
 
 /**
-* Returns the standard deviation of a Cosine distribution.
+* Returns the mode for a raised cosine distribution with location `mu` and scale `s`.
 *
 * @param mu   location parameter
 * @param s    scale parameter
@@ -33,9 +33,10 @@
 * // returns ~0.362
 */
 double stdlib_base_dists_cosine_stdev( const double mu, const double s ) {
-	if ( stdlib_base_is_nan( mu ) ||
-		 stdlib_base_is_nan( s ) ||
-		 s <= 0.0
+	if ( 
+		stdlib_base_is_nan( mu ) ||
+		stdlib_base_is_nan( s ) ||
+		s <= 0.0
 	) {
 		return 0.0/0.0; // NaN
 	}