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mndaxpy.cxx
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1 // @(#)root/minuit2:$Id$
2 // Authors: M. Winkler, F. James, L. Moneta, A. Zsenei 2003-2005
3 
4 /**********************************************************************
5  * *
6  * Copyright (c) 2005 LCG ROOT Math team, CERN/PH-SFT *
7  * *
8  **********************************************************************/
9 
10 /* daxpy.f -- translated by f2c (version 20010320).
11  You must link the resulting object file with the libraries:
12  -lf2c -lm (in that order)
13 */
14 
15 namespace ROOT {
16 
17  namespace Minuit2 {
18 
19 
20 int Mndaxpy(unsigned int n, double da, const double* dx, int incx, double* dy,
21  int incy) {
22  /* System generated locals */
23  int i__1;
24 
25  /* Local variables */
26  int i__, m, ix, iy, mp1;
27 
28 
29  /* constant times a vector plus a vector. */
30  /* uses unrolled loops for increments equal to one. */
31  /* jack dongarra, linpack, 3/11/78. */
32  /* modified 12/3/93, array(1) declarations changed to array(*) */
33 
34 
35  /* Parameter adjustments */
36  --dy;
37  --dx;
38 
39  /* Function Body */
40  if (n <= 0) {
41  return 0;
42  }
43  if (da == 0.) {
44  return 0;
45  }
46  if (incx == 1 && incy == 1) {
47  goto L20;
48  }
49 
50  /* code for unequal increments or equal increments */
51  /* not equal to 1 */
52 
53  ix = 1;
54  iy = 1;
55  if (incx < 0) {
56  ix = (-static_cast<int>(n) + 1) * incx + 1;
57  }
58  if (incy < 0) {
59  iy = (-static_cast<int>(n) + 1) * incy + 1;
60  }
61  i__1 = n;
62  for (i__ = 1; i__ <= i__1; ++i__) {
63  dy[iy] += da * dx[ix];
64  ix += incx;
65  iy += incy;
66  /* L10: */
67  }
68  return 0;
69 
70  /* code for both increments equal to 1 */
71 
72 
73  /* clean-up loop */
74 
75 L20:
76  m = n % 4;
77  if (m == 0) {
78  goto L40;
79  }
80  i__1 = m;
81  for (i__ = 1; i__ <= i__1; ++i__) {
82  dy[i__] += da * dx[i__];
83  /* L30: */
84  }
85  if (n < 4) {
86  return 0;
87  }
88 L40:
89  mp1 = m + 1;
90  i__1 = n;
91  for (i__ = mp1; i__ <= i__1; i__ += 4) {
92  dy[i__] += da * dx[i__];
93  dy[i__ + 1] += da * dx[i__ + 1];
94  dy[i__ + 2] += da * dx[i__ + 2];
95  dy[i__ + 3] += da * dx[i__ + 3];
96  /* L50: */
97  }
98  return 0;
99 } /* daxpy_ */
100 
101 
102  } // namespace Minuit2
103 
104 } // namespace ROOT
m
auto * m
Definition: textangle.C:8
n
const Int_t n
Definition: legend1.C:16
ROOT::Minuit2::Mndaxpy
int Mndaxpy(unsigned int, double, const double *, int, double *, int)
Definition: mndaxpy.cxx:28
ROOT
VSD Structures.
Definition: StringConv.hxx:21