test: add test cases for blas/base/dtrsv

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---

Author: ShabiShett07

lib/node_modules/@stdlib/blas/base/dtrsv/test/fixtures/column_major_ox.json

@@ -0,0 +1,16 @@
+{
+  "order": "column-major",
+  "trans": "no-transpose",
+  "diag": "unit",
+  "uplo": "lower",
+  "strideX": 1,
+  "offsetA": 0,
+  "offsetX": 2,
+  "LDA": 3,
+  "strideA1": 1,
+  "strideA2": 3,
+  "N": 3,
+  "A": [ 1.0, 2.0, 2.0, 0.0, 1.0, 1.0, 0.0, 0.0, 1.0 ],
+  "x": [ 0.0, 0.0, 1.0, 2.0, 3.0 ],
+  "x_out": [ 0.0, 0.0, 1.0, 0.0, 1.0 ]
+}

lib/node_modules/@stdlib/blas/base/dtrsv/test/fixtures/row_major_ox.json

@@ -0,0 +1,16 @@
+{
+  "order": "row-major",
+  "trans": "no-transpose",
+  "diag": "unit",
+  "uplo": "lower",
+  "strideX": 1,
+  "offsetA": 0,
+  "offsetX": 2,
+  "LDA": 3,
+  "strideA1": 3,
+  "strideA2": 1,
+  "N": 3,
+  "A": [ 1.0, 0.0, 0.0, 2.0, 1.0, 0.0, 2.0, 1.0, 1.0 ],
+  "x": [ 0.0, 0.0, 1.0, 2.0, 3.0 ],
+  "x_out": [ 0.0, 0.0, 1.0, 0.0, 1.0 ]
+}

lib/node_modules/@stdlib/blas/base/dtrsv/test/test.ndarray.js

@@ -40,6 +40,7 @@ var rutu = require( './fixtures/row_major_u_t_u.json' );
 var rxt = require( './fixtures/row_major_xt.json' );
 var rxn = require( './fixtures/row_major_xn.json' );
 var roa = require( './fixtures/row_major_oa.json' );
+var rox = require( './fixtures/row_major_ox.json' );
 var rsa1sa2 = require( './fixtures/row_major_sa1_sa2.json' );
 var rsa1nsa2 = require( './fixtures/row_major_sa1n_sa2.json' );
 var rsa1sa2n = require( './fixtures/row_major_sa1_sa2n.json' );
@@ -57,6 +58,7 @@ var cutu = require( './fixtures/column_major_u_t_u.json' );
 var cxt = require( './fixtures/column_major_xt.json' );
 var cxn = require( './fixtures/column_major_xn.json' );
 var coa = require( './fixtures/column_major_oa.json' );
+var cox = require( './fixtures/column_major_ox.json' );
 var csa1sa2 = require( './fixtures/column_major_sa1_sa2.json' );
 var csa1nsa2 = require( './fixtures/column_major_sa1n_sa2.json' );
 var csa1sa2n = require( './fixtures/column_major_sa1_sa2n.json' );
@@ -938,6 +940,48 @@ tape( 'the function supports a negative `x` stride (column-major)', function tes
 	t.end();
 });
 
+tape( 'the function supports an `x` offset (row-major)', function test( t ) {
+	var expected;
+	var data;
+	var out;
+	var a;
+	var x;
+
+	data = rox;
+
+	a = new Float64Array( data.A );
+	x = new Float64Array( data.x );
+
+	expected = new Float64Array( data.x_out );
+
+	out = dtrsv( data.uplo, data.trans, data.diag, data.N, a, data.strideA1, data.strideA2, data.offsetA, x, data.strideX, data.offsetX );
+	t.strictEqual( out, x, 'returns expected value' );
+	t.deepEqual( out, expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function supports an `x` offset (column-major)', function test( t ) {
+	var expected;
+	var data;
+	var out;
+	var a;
+	var x;
+
+	data = cox;
+
+	a = new Float64Array( data.A );
+	x = new Float64Array( data.x );
+
+	expected = new Float64Array( data.x_out );
+
+	out = dtrsv( data.uplo, data.trans, data.diag, data.N, a, data.strideA1, data.strideA2, data.offsetA, x, data.strideX, data.offsetX );
+	t.strictEqual( out, x, 'returns expected value' );
+	t.deepEqual( out, expected, 'returns expected value' );
+
+	t.end();
+});
+
 tape( 'the function supports complex access patterns (row-major)', function test( t ) {
 	var expected;
 	var data;