updates to comments/docs and start of cpp interface for optional argu…

…ments

daxpy.f

@@ -1,70 +1,70 @@
-      SUBROUTINE DAXPY(N,DA,DX,INCX,DY,INCY)
-*     .. Scalar Arguments ..
-      DOUBLE PRECISION DA
-      INTEGER INCX,INCY,N
-*     ..
-*     .. Array Arguments ..
-      DOUBLE PRECISION DX(*),DY(*)
-*     ..
-*
-*  Purpose
-*  =======
-*
-*     DAXPY constant times a vector plus a vector.
-*     uses unrolled loops for increments equal to one.
-*
-*  Further Details
-*  ===============
-*
-*     jack dongarra, linpack, 3/11/78.
-*     modified 12/3/93, array(1) declarations changed to array(*)
-*
-*  =====================================================================
-*
-*     .. Local Scalars ..
-      INTEGER I,IX,IY,M,MP1
-*     ..
-*     .. Intrinsic Functions ..
-      INTRINSIC MOD
-*     ..
-      IF (N.LE.0) RETURN
-      IF (DA.EQ.0.0d0) RETURN
-      IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN
-*
-*        code for both increments equal to 1
-*
-*
-*        clean-up loop
-*
-         M = MOD(N,4)
-         IF (M.NE.0) THEN
-            DO I = 1,M
-               DY(I) = DY(I) + DA*DX(I)
-            END DO
-         END IF
-         IF (N.LT.4) RETURN
-         MP1 = M + 1
-         DO I = MP1,N,4
-            DY(I) = DY(I) + DA*DX(I)
-            DY(I+1) = DY(I+1) + DA*DX(I+1)
-            DY(I+2) = DY(I+2) + DA*DX(I+2)
-            DY(I+3) = DY(I+3) + DA*DX(I+3)
-         END DO
-      ELSE
-*
-*        code for unequal increments or equal increments
-*          not equal to 1
-*
-         IX = 1
-         IY = 1
-         IF (INCX.LT.0) IX = (-N+1)*INCX + 1
-         IF (INCY.LT.0) IY = (-N+1)*INCY + 1
-         DO I = 1,N
-          DY(IY) = DY(IY) + DA*DX(IX)
-          IX = IX + INCX
-          IY = IY + INCY
-         END DO
-      END IF
-      RETURN
+      SUBROUTINE DAXPY(N, DA, DX, INCX, DY, INCY)
+          *..Scalar Arguments..
+          DOUBLE PRECISION DA
+          INTEGER INCX, INCY, N
+          *..
+          *..Array Arguments..
+          DOUBLE PRECISION DX(*), DY(*)
+          *..
+          *
+          *Purpose
+          * ==  ==  == =
+          *
+          *DAXPY constant times a vector plus a vector.
+          *uses unrolled loops for increments equal to one.
+          *
+          *Further Details
+          * ==  ==  ==  ==  ==  ==  == =
+          *
+          *jack dongarra, linpack, 3/11/78.
+          *modified 12/3/93, array(1) declarations changed to array(*)
+          *
+          *  =====================================================================
+          *
+          *..Local Scalars..
+          INTEGER I, IX, IY, M, MP1
+          *..
+          *..Intrinsic Functions..
+          INTRINSIC MOD
+          *..
+          IF (N .LE. 0) RETURN
+          IF (DA .EQ. 0.0d0) RETURN
+          IF (INCX .EQ. 1 .AND. INCY .EQ. 1) THEN
+              *
+              *code for both increments equal to 1
+              *
+              *
+              *clean - up loop
+              *
+              M = MOD(N, 4)
+              IF (M .NE. 0) THEN
+                  DO I = 1, M
+                      DY(I) = DY(I) + DA*DX(I)
+                  END DO
+              END IF
+              IF (N .LT. 4) RETURN
+              MP1 = M + 1
+              DO I = MP1, N, 4
+                  DY(I) = DY(I) + DA*DX(I)
+                  DY(I + 1) = DY(I + 1) + DA*DX(I + 1)
+                  DY(I + 2) = DY(I + 2) + DA*DX(I + 2)
+                  DY(I + 3) = DY(I + 3) + DA*DX(I + 3)
+              END DO
+          ELSE
+              *
+              *code for unequal increments or equal increments
+              *not equal to 1
+              *
+              IX = 1
+              IY = 1
+              IF (INCX .LT. 0) IX = (-N + 1)*INCX + 1
+              IF (INCY .LT. 0) IY = (-N + 1)*INCY + 1
+              DO I = 1, N
+                  DY(IY) = DY(IY) + DA*DX(IX)
+                  IX = IX + INCX
+                  IY = IY + INCY
+              END DO
+          END IF
+          RETURN
       END