chore: fixed test cases for variancetk refactoring

Added accessor tests for refactoring variancetk

Fixes: #5690
Co-authored-by: Prajjwal Bajpai <[email protected]>

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---

Author: prajjwalbajpai

lib/node_modules/@stdlib/stats/base/variancetk/test/test.main.js

@@ -68,11 +68,11 @@ tape( 'the function calculates the sample variance of a strided array (accessors
 	t.strictEqual( v, 53.5/(x.length-1), 'returns expected value' );
 
 	x = [ -4.0, -4.0 ];
-	v = variancetk( x.length, 1, x, 1 );
+	v = variancetk( x.length, 1, toAccessorArray( x ), 1 );
 	t.strictEqual( v, 0.0, 'returns expected value' );
 
 	x = [ NaN, 4.0 ];
-	v = variancetk( x.length, 1, x, 1 );
+	v = variancetk( x.length, 1, toAccessorArray( x ), 1 );
 	t.strictEqual( isnan( v ), true, 'returns expected value' );
 
 	t.end();

lib/node_modules/@stdlib/stats/base/variancetk/test/test.ndarray.js

@@ -58,6 +58,25 @@ tape( 'the function calculates the population variance of a strided array', func
 	t.end();
 });
 
+tape( 'the function calculates the population variance of a strided array (accessors)', function test( t ) {
+	var x;
+	var v;
+
+	x = [ 1.0, -2.0, -4.0, 5.0, 0.0, 3.0 ];
+	v = variancetk( x.length, 0, toAccessorArray( x ), 1, 0 );
+	t.strictEqual( v, 53.5/x.length, 'returns expected value' );
+
+	x = [ -4.0, -4.0 ];
+	v = variancetk( x.length, 0, toAccessorArray( x ), 1, 0 );
+	t.strictEqual( v, 0.0, 'returns expected value' );
+
+	x = [ NaN, 4.0 ];
+	v = variancetk( x.length, 0, toAccessorArray( x ), 1, 0 );
+	t.strictEqual( isnan( v ), true, 'returns expected value' );
+
+	t.end();
+});
+
 tape( 'the function calculates the sample variance of a strided array', function test( t ) {
 	var x;
 	var v;