feat: add branch 3 logic in base.js

Author: DivitJain26

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

@@ -62,10 +62,11 @@ function ctpmv( order, uplo, trans, diag, N, AP, strideAP, offsetAP, x, strideX,
 	var imtmp;
 	var isrm;
 	var sign;
-	var rea;
-	var ima;
+	var imx;
 	var rex;
 	var imx;
+	var rea;
+	var ima;
 	var iap;
 	var ix0;
 	var ix1;
@@ -171,6 +172,43 @@ function ctpmv( order, uplo, trans, diag, N, AP, strideAP, offsetAP, x, strideX,
 		}
 		return x;
 	}
+	if (
+		( !isrm && uplo === 'upper' && trans !== 'no-transpose' ) ||
+		( isrm && uplo === 'lower' && trans === 'no-transpose' )
+	) {
+		kk += ( ( N * ( N + 1 ) / 2 ) - 1 ) * sap;
+		ix1 = ox + ( ( N - 1 ) * sx );
+		for ( i1 = N - 1; i1 >= 0; i1-- ) {
+			rex = viewX[ ix1 ];
+			imx = viewX[ ix1 + 1 ];
+			iap = kk;
+			ix0 = ix1;
+			if ( nonunit ) {
+				rea = viewAP[ iap ];
+				ima = sign * viewAP[ iap + 1 ];
+				retmp = f32( ( rea * rex ) - ( ima * imx ) );
+				imtmp = f32( ( rea * imx ) + ( ima * rex ) );
+			} else {
+				retmp = rex;
+				imtmp = imx;
+			}
+			for ( i0 = i1 - 1; i0 >= 0; i0-- ) {
+				ix0 -= sx;
+				iap -= sap;
+				rea = viewAP[ iap ];
+				ima = sign * viewAP[ iap + 1 ];
+				rex = viewX[ ix0 ];
+				imx = viewX[ ix0 + 1 ];
+				retmp += f32( ( rea * rex ) - ( ima * imx ) );
+				imtmp += f32( ( rea * imx ) + ( ima * rex ) );
+			}
+			viewX[ ix1 ] = retmp;
+			viewX[ ix1 + 1 ] = imtmp;
+			ix1 -= sx;
+			kk -= ( i1 + 1 ) * sap;
+		}
+		return x;
+	}
 }