git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@7435 f3b2605a-c512-4ea7-a41b-209d697bcdaa

lib/linalg/dcopy.f

@@ -0,0 +1,68 @@
+      SUBROUTINE DCOPY(N,DX,INCX,DY,INCY)
+*     .. Scalar Arguments ..
+      INTEGER INCX,INCY,N
+*     ..
+*     .. Array Arguments ..
+      DOUBLE PRECISION DX(*),DY(*)
+*     ..
+*
+*  Purpose
+*  =======
+*
+*     DCOPY copies a vector, x, to a vector, y.
+*     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 (INCX.EQ.1 .AND. INCY.EQ.1) GO TO 20
+*
+*        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 10 I = 1,N
+          DY(IY) = DX(IX)
+          IX = IX + INCX
+          IY = IY + INCY
+   10 CONTINUE
+      RETURN
+*
+*        code for both increments equal to 1
+*
+*
+*        clean-up loop
+*
+   20 M = MOD(N,7)
+      IF (M.EQ.0) GO TO 40
+      DO 30 I = 1,M
+          DY(I) = DX(I)
+   30 CONTINUE
+      IF (N.LT.7) RETURN
+   40 MP1 = M + 1
+      DO 50 I = MP1,N,7
+          DY(I) = DX(I)
+          DY(I+1) = DX(I+1)
+          DY(I+2) = DX(I+2)
+          DY(I+3) = DX(I+3)
+          DY(I+4) = DX(I+4)
+          DY(I+5) = DX(I+5)
+          DY(I+6) = DX(I+6)
+   50 CONTINUE
+      RETURN
+      END