refactor: simplify loop

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

Author: kgryte

lib/node_modules/@stdlib/ndarray/base/append-singleton-dimensions/lib/main.js

@@ -53,6 +53,7 @@ function appendSingletonDimensions( x, n, writable ) {
 	var sh;
 	var st;
 	var N;
+	var s;
 	var i;
 
 	sh = getShape( x, false );
@@ -68,13 +69,10 @@ function appendSingletonDimensions( x, n, writable ) {
 		strides.push( st[ i ] );
 	}
 	// Append singleton dimensions...
+	s = ( N > 0 ) ? st[ N-1 ] : st[ 0 ];
 	for ( i = 0; i < n; i++ ) {
 		shape.push( 1 );
-		if ( N > 0 ) {
-			strides.push( st[ N-1 ] );
-		} else {
-			strides.push( st[ 0 ] );
-		}
+		strides.push( s );
 	}
 	return new x.constructor( getDType( x ), getData( x ), shape, strides, getOffset( x ), getOrder( x ), { // eslint-disable-line max-len
 		'readonly': !writable