docs: add examples and keywords

lib/node_modules/@stdlib/math/base/special/ellipj/package.json

@@ -51,5 +51,19 @@
     "win32",
     "windows"
   ],
-  "keywords": []
+  "keywords": [
+    "stdlib",
+    "stdmath",
+    "mathematics",
+    "math",
+    "special",
+    "elliptic",
+    "jacobi",
+    "sn",
+    "cn",
+    "dn",
+    "am",
+    "amplitude",
+    "number"
+  ]
 }

lib/node_modules/@stdlib/math/base/special/log2/src/main.c

@@ -48,6 +48,10 @@ static const int32_t HIGH_BIASED_EXP_0 = 0x3ff00000;
 *
 * @param x    input value
 * @return     output value
+*
+* @example
+* double out = stdlib_base_log2( 4.0 );
+* // returns 2.0
 */
 double stdlib_base_log2( const double x ) {
 	double valLo;

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

@@ -26,6 +26,13 @@
 * @param x         input value (in degrees)
 * @param sine      destination to store the sine
 * @param cosine    destination to store the cosine
+*
+* @example
+* float x = 0.0f;
+*
+* float cosine;
+* float sine;
+* stdlib_base_sincosdf( x, &sine, &cosine );
 */
 void stdlib_base_sincosdf( const float x, float* sine, float* cosine ) {
 	*sine = stdlib_base_sindf( x );