refactor: explicitly return zero for non-integer x

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Author: Planeshifter

lib/node_modules/@stdlib/stats/base/dists/signrank/pdf/lib/factory.js

@@ -22,6 +22,7 @@
 
 var isPositiveInteger = require( '@stdlib/math/base/assert/is-positive-integer' );
 var constantFunction = require( '@stdlib/utils/constant-function' );
+var isInteger = require( '@stdlib/math/base/assert/is-integer' );
 var isfinite = require( '@stdlib/math/base/assert/is-finite' );
 var isnan = require( '@stdlib/math/base/assert/is-nan' );
 var exp = require( '@stdlib/math/base/special/exp' );
@@ -69,6 +70,9 @@ function factory( n ) {
 		if ( isnan( x ) ) {
 			return NaN;
 		}
+		if ( !isInteger( x ) ) {
+			return 0.0;
+		}
 		if ( x < 0.0 || x > mlim ) {
 			return 0.0;
 		}

lib/node_modules/@stdlib/stats/base/dists/signrank/pdf/lib/main.js

@@ -21,6 +21,7 @@
 // MODULES //
 
 var isPositiveInteger = require( '@stdlib/math/base/assert/is-positive-integer' );
+var isInteger = require( '@stdlib/math/base/assert/is-integer' );
 var isfinite = require( '@stdlib/math/base/assert/is-finite' );
 var isnan = require( '@stdlib/math/base/assert/is-nan' );
 var exp = require( '@stdlib/math/base/special/exp' );
@@ -75,6 +76,9 @@ function pdf( x, n ) {
 	) {
 		return NaN;
 	}
+	if ( !isInteger( x ) ) {
+		return 0.0;
+	}
 	mlim = ( n * ( n + 1 ) ) / 2;
 	if ( x < 0.0 || x > mlim ) {
 		return 0.0;

lib/node_modules/@stdlib/stats/base/dists/signrank/pdf/test/test.factory.js

@@ -107,6 +107,20 @@ tape( 'if not provided a positive integer for `n`, the created function always r
 	t.end();
 });
 
+tape( 'the created function returns `0` if provided a non-integer for `x`', function test( t ) {
+	var pdf = factory( 8 );
+	var y = pdf( 1.5 );
+	t.equal( y, 0.0, 'returns expected value' );
+
+	y = pdf( 2.5 );
+	t.equal( y, 0.0, 'returns expected value' );
+
+	y = pdf( 0.1 );
+	t.equal( y, 0.0, 'returns expected value' );
+
+	t.end();
+});
+
 tape( 'the created function evaluates the PDF for `x` given `n` observations', function test( t ) {
 	var expected;
 	var delta;

lib/node_modules/@stdlib/stats/base/dists/signrank/pdf/test/test.pdf.js

@@ -80,6 +80,18 @@ tape( 'if not provided a positive integer for `n`, the function returns `NaN`',
 	t.end();
 });
 
+tape( 'the function returns `0` if provided a non-integer for `x`', function test( t ) {
+	var y = pdf( 1.5, 8 );
+	t.equal( y, 0.0, 'returns expected value' );
+	t.end();
+
+	y = pdf( 2.5, 8 );
+	t.equal( y, 0.0, 'returns expected value' );
+
+	y = pdf( 0.1, 4 );
+	t.equal( y, 0.0, 'returns expected value' );
+});
+
 tape( 'the function evaluates the PDF for `x` given `n` observations', function test( t ) {
 	var expected;
 	var delta;