feat: add branch 1 logic in base.js

Author: DivitJain26

lib/node_modules/@stdlib/blas/base/ctpmv/lib/base.js

@@ -14,4 +14,132 @@
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
-*/
+*/
+
+'use strict';
+
+// MODULES //
+
+var isRowMajor = require( '@stdlib/ndarray/base/assert/is-row-major-string' );
+var f32 = require( '@stdlib/number/float64/base/to-float32' );
+var reinterpret = require( '@stdlib/strided/base/reinterpret-complex64' );
+var muladd = require( '@stdlib/complex/float32/base/mul-add' ).assign;
+
+
+// MAIN //
+
+/**
+* Performs one of the matrix-vector operations `x = A*x`, or `x = A**T*x`, or `x = A**H*x`, where `x` is an `N` element vector and `A` is an `N` by `N` unit, or non-unit, upper or lower triangular matrix, supplied in packed form.
+*
+* @private
+* @param {string} order - storage layout
+* @param {string} uplo - specifies whether `A` is an upper or lower triangular matrix
+* @param {string} trans - specifies whether `A` should be transposed, conjugate-transposed, or not transposed
+* @param {string} diag - specifies whether `A` has a unit diagonal
+* @param {NonNegativeInteger} N - number of elements along each dimension of `A`
+* @param {Complex64Array} AP - packed form of a symmetric matrix `A`
+* @param {integer} strideAP - `AP` stride length
+* @param {NonNegativeInteger} offsetAP - starting index for `AP`
+* @param {Complex64Array} x - input vector
+* @param {integer} strideX - `x` stride length
+* @param {NonNegativeInteger} offsetX - starting index for `x`
+* @returns {Complex64Array} `x`
+*
+* @example
+* var Complex64Array = require( '@stdlib/array/float64' );
+*
+* var AP = new Complex64Array( [  ] );
+* var x = new Complex64Array( [  ] );
+*
+* ctpmv( 'row-major', 'upper', 'no-transpose', 'unit', 3, AP, 1, 0, x, 1, 0 );
+* // x => <Complex64Array>[  ]
+*/
+function ctpmv( order, uplo, trans, diag, N, AP, strideAP, offsetAP, x, strideX, offsetX ) { // eslint-disable-line max-params, max-len
+	var nonunit;
+	var viewAP;
+	var viewX;
+	var retmp;
+	var imtmp;
+	var isrm;
+	var sign;
+	var rea;
+	var ima;
+	var rex;
+	var imx;
+	var iap;
+	var ix0;
+	var ix1;
+	var sap;
+	var kk;
+	var ox;
+	var sx;
+	var re;
+	var im;
+	var i0;
+	var i1;
+
+	// Layout
+	isrm = isRowMajor( order );
+
+	// Diagonal
+	nonunit = ( diag === 'non-unit' );
+
+	// Reinterpret arrays to raw numeric views
+	viewAP = reinterpret( AP, 0 );
+	viewX = reinterpret( x, 0 );
+
+	// Adjust sign to account for conjugation
+	if ( trans === 'conjugate-transpose' ) {
+		sign = -1;
+	} else {
+		sign = 1;
+	}
+
+	// Vector indexing base
+	ox = offsetX * 2;
+	kk = offsetAP * 2;
+
+	// Vector strides
+	sx = strideX * 2;
+	sap = strideAP * 2;
+
+	if (
+		( !isrm && trans === 'no-transpose' && uplo === 'upper' ) ||
+		( isrm && trans !== 'no-transpose' && uplo === 'lower' )
+	) {
+		ix1 = ox;
+		for ( i1 = 0; i1 < N; i1++ ) {
+			retmp = viewX[ ix1 ];
+			imtmp = viewX[ ix1 + 1 ];
+			if (retmp !== 0.0 || imtmp !== 0.0) {
+				iap = kk;
+				ix0 = ox;
+				for ( i0 = 0; i0 < i1; i0++ ) {
+					rea = viewAP[ iap ];
+					ima = sign * viewAP[ iap + 1 ];
+					rex = viewX[ ix0 ];
+					imx = viewX[ ix0 + 1 ];
+					muladd( rea, ima, retmp, imtmp, rex, imx, viewX, 1, ix0 );
+					iap += sap;
+					ix0 += sx;
+				}
+				if ( nonunit ) {
+					rea = viewAP[ iap ];
+					ima = sign * viewAP[ iap + 1 ];
+					rex = viewX[ ix0 ];
+					imx = viewX[ ix0 + 1 ];
+					viewX[ ix0 ] = f32( ( rea * rex ) - ( ima * imx ) );
+					viewX[ ix0 + 1 ] = f32( ( rea * imx ) + ( ima * rex ) );
+				}
+			}
+			ix1 += sx;
+			kk += ( i1 + 1 ) * sap;
+		}
+		return x;
+	}
+}
+
+
+// EXPORTS //
+
+module.exports = ctpmv;