--- rpl/lapack/blas/izamax.f	2010/08/06 15:32:20	1.3
+++ rpl/lapack/blas/izamax.f	2023/08/07 08:38:44	1.18
@@ -1,27 +1,89 @@
+*> \brief \b IZAMAX
+*
+*  =========== DOCUMENTATION ===========
+*
+* Online html documentation available at
+*            http://www.netlib.org/lapack/explore-html/
+*
+*  Definition:
+*  ===========
+*
+*       INTEGER FUNCTION IZAMAX(N,ZX,INCX)
+*
+*       .. Scalar Arguments ..
+*       INTEGER INCX,N
+*       ..
+*       .. Array Arguments ..
+*       COMPLEX*16 ZX(*)
+*       ..
+*
+*
+*> \par Purpose:
+*  =============
+*>
+*> \verbatim
+*>
+*>    IZAMAX finds the index of the first element having maximum |Re(.)| + |Im(.)|
+*> \endverbatim
+*
+*  Arguments:
+*  ==========
+*
+*> \param[in] N
+*> \verbatim
+*>          N is INTEGER
+*>         number of elements in input vector(s)
+*> \endverbatim
+*>
+*> \param[in] ZX
+*> \verbatim
+*>          ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
+*> \endverbatim
+*>
+*> \param[in] INCX
+*> \verbatim
+*>          INCX is INTEGER
+*>         storage spacing between elements of ZX
+*> \endverbatim
+*
+*  Authors:
+*  ========
+*
+*> \author Univ. of Tennessee
+*> \author Univ. of California Berkeley
+*> \author Univ. of Colorado Denver
+*> \author NAG Ltd.
+*
+*> \ingroup aux_blas
+*
+*> \par Further Details:
+*  =====================
+*>
+*> \verbatim
+*>
+*>     jack dongarra, 1/15/85.
+*>     modified 3/93 to return if incx .le. 0.
+*>     modified 12/3/93, array(1) declarations changed to array(*)
+*> \endverbatim
+*>
+*  =====================================================================
       INTEGER FUNCTION IZAMAX(N,ZX,INCX)
+*
+*  -- Reference BLAS level1 routine --
+*  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
+*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
+*
 *     .. Scalar Arguments ..
       INTEGER INCX,N
 *     ..
 *     .. Array Arguments ..
-      DOUBLE COMPLEX ZX(*)
+      COMPLEX*16 ZX(*)
 *     ..
 *
-*  Purpose
-*  =======
-*
-*     IZAMAX finds the index of element having max. absolute value.
-*
-*  Further Details
-*  ===============
-*
-*     jack dongarra, 1/15/85.
-*     modified 3/93 to return if incx .le. 0.
-*     modified 12/3/93, array(1) declarations changed to array(*)
-*
 *  =====================================================================
 *
 *     .. Local Scalars ..
-      DOUBLE PRECISION SMAX
+      DOUBLE PRECISION DMAX
       INTEGER I,IX
 *     ..
 *     .. External Functions ..
@@ -32,28 +94,34 @@
       IF (N.LT.1 .OR. INCX.LE.0) RETURN
       IZAMAX = 1
       IF (N.EQ.1) RETURN
-      IF (INCX.EQ.1) GO TO 20
+      IF (INCX.EQ.1) THEN
+*
+*        code for increment equal to 1
+*
+         DMAX = DCABS1(ZX(1))
+         DO I = 2,N
+            IF (DCABS1(ZX(I)).GT.DMAX) THEN
+               IZAMAX = I
+               DMAX = DCABS1(ZX(I))
+            END IF
+         END DO
+      ELSE
 *
 *        code for increment not equal to 1
 *
-      IX = 1
-      SMAX = DCABS1(ZX(1))
-      IX = IX + INCX
-      DO 10 I = 2,N
-          IF (DCABS1(ZX(IX)).LE.SMAX) GO TO 5
-          IZAMAX = I
-          SMAX = DCABS1(ZX(IX))
-    5     IX = IX + INCX
-   10 CONTINUE
+         IX = 1
+         DMAX = DCABS1(ZX(1))
+         IX = IX + INCX
+         DO I = 2,N
+            IF (DCABS1(ZX(IX)).GT.DMAX) THEN
+               IZAMAX = I
+               DMAX = DCABS1(ZX(IX))
+            END IF
+            IX = IX + INCX
+         END DO
+      END IF
       RETURN
 *
-*        code for increment equal to 1
+*     End of IZAMAX
 *
-   20 SMAX = DCABS1(ZX(1))
-      DO 30 I = 2,N
-          IF (DCABS1(ZX(I)).LE.SMAX) GO TO 30
-          IZAMAX = I
-          SMAX = DCABS1(ZX(I))
-   30 CONTINUE
-      RETURN
       END