ergo
template_lapack_laruv.h
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1 /* Ergo, version 3.3, a program for linear scaling electronic structure
2  * calculations.
3  * Copyright (C) 2013 Elias Rudberg, Emanuel H. Rubensson, and Pawel Salek.
4  *
5  * This program is free software: you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation, either version 3 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program. If not, see <http://www.gnu.org/licenses/>.
17  *
18  * Primary academic reference:
19  * Kohn−Sham Density Functional Theory Electronic Structure Calculations
20  * with Linearly Scaling Computational Time and Memory Usage,
21  * Elias Rudberg, Emanuel H. Rubensson, and Pawel Salek,
22  * J. Chem. Theory Comput. 7, 340 (2011),
23  * <http://dx.doi.org/10.1021/ct100611z>
24  *
25  * For further information about Ergo, see <http://www.ergoscf.org>.
26  */
27 
28  /* This file belongs to the template_lapack part of the Ergo source
29  * code. The source files in the template_lapack directory are modified
30  * versions of files originally distributed as CLAPACK, see the
31  * Copyright/license notice in the file template_lapack/COPYING.
32  */
33 
34 
35 #ifndef TEMPLATE_LAPACK_LARUV_HEADER
36 #define TEMPLATE_LAPACK_LARUV_HEADER
37 
38 
39 template<class Treal>
40 int dlaruv_(integer *iseed, const integer *n, Treal *x)
41 {
42 /* -- LAPACK auxiliary routine (version 3.0) --
43  Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
44  Courant Institute, Argonne National Lab, and Rice University
45  October 31, 1992
46 
47 
48  Purpose
49  =======
50 
51  DLARUV returns a vector of n random real numbers from a uniform (0,1)
52  distribution (n <= 128).
53 
54  This is an auxiliary routine called by DLARNV and ZLARNV.
55 
56  Arguments
57  =========
58 
59  ISEED (input/output) INTEGER array, dimension (4)
60  On entry, the seed of the random number generator; the array
61  elements must be between 0 and 4095, and ISEED(4) must be
62  odd.
63  On exit, the seed is updated.
64 
65  N (input) INTEGER
66  The number of random numbers to be generated. N <= 128.
67 
68  X (output) DOUBLE PRECISION array, dimension (N)
69  The generated random numbers.
70 
71  Further Details
72  ===============
73 
74  This routine uses a multiplicative congruential method with modulus
75  2**48 and multiplier 33952834046453 (see G.S.Fishman,
76  'Multiplicative congruential random number generators with modulus
77  2**b: an exhaustive analysis for b = 32 and a partial analysis for
78  b = 48', Math. Comp. 189, pp 331-344, 1990).
79 
80  48-bit integers are stored in 4 integer array elements with 12 bits
81  per element. Hence the routine is portable across machines with
82  integers of 32 bits or more.
83 
84  =====================================================================
85 
86  Parameter adjustments */
87  /* Initialized data */
88  integer mm[512] /* was [128][4] */ = { 494,2637,255,2008,1253,
89  3344,4084,1739,3143,3468,688,1657,1238,3166,1292,3422,1270,2016,
90  154,2862,697,1706,491,931,1444,444,3577,3944,2184,1661,3482,657,
91  3023,3618,1267,1828,164,3798,3087,2400,2870,3876,1905,1593,1797,
92  1234,3460,328,2861,1950,617,2070,3331,769,1558,2412,2800,189,287,
93  2045,1227,2838,209,2770,3654,3993,192,2253,3491,2889,2857,2094,
94  1818,688,1407,634,3231,815,3524,1914,516,164,303,2144,3480,119,
95  3357,837,2826,2332,2089,3780,1700,3712,150,2000,3375,1621,3090,
96  3765,1149,3146,33,3082,2741,359,3316,1749,185,2784,2202,2199,1364,
97  1244,2020,3160,2785,2772,1217,1822,1245,2252,3904,2774,997,2573,
98  1148,545,322,789,1440,752,2859,123,1848,643,2405,2638,2344,46,
99  3814,913,3649,339,3808,822,2832,3078,3633,2970,637,2249,2081,4019,
100  1478,242,481,2075,4058,622,3376,812,234,641,4005,1122,3135,2640,
101  2302,40,1832,2247,2034,2637,1287,1691,496,1597,2394,2584,1843,336,
102  1472,2407,433,2096,1761,2810,566,442,41,1238,1086,603,840,3168,
103  1499,1084,3438,2408,1589,2391,288,26,512,1456,171,1677,2657,2270,
104  2587,2961,1970,1817,676,1410,3723,2803,3185,184,663,499,3784,1631,
105  1925,3912,1398,1349,1441,2224,2411,1907,3192,2786,382,37,759,2948,
106  1862,3802,2423,2051,2295,1332,1832,2405,3638,3661,327,3660,716,
107  1842,3987,1368,1848,2366,2508,3754,1766,3572,2893,307,1297,3966,
108  758,2598,3406,2922,1038,2934,2091,2451,1580,1958,2055,1507,1078,
109  3273,17,854,2916,3971,2889,3831,2621,1541,893,736,3992,787,2125,
110  2364,2460,257,1574,3912,1216,3248,3401,2124,2762,149,2245,166,466,
111  4018,1399,190,2879,153,2320,18,712,2159,2318,2091,3443,1510,449,
112  1956,2201,3137,3399,1321,2271,3667,2703,629,2365,2431,1113,3922,
113  2554,184,2099,3228,4012,1921,3452,3901,572,3309,3171,817,3039,
114  1696,1256,3715,2077,3019,1497,1101,717,51,981,1978,1813,3881,76,
115  3846,3694,1682,124,1660,3997,479,1141,886,3514,1301,3604,1888,
116  1836,1990,2058,692,1194,20,3285,2046,2107,3508,3525,3801,2549,
117  1145,2253,305,3301,1065,3133,2913,3285,1241,1197,3729,2501,1673,
118  541,2753,949,2361,1165,4081,2725,3305,3069,3617,3733,409,2157,
119  1361,3973,1865,2525,1409,3445,3577,77,3761,2149,1449,3005,225,85,
120  3673,3117,3089,1349,2057,413,65,1845,697,3085,3441,1573,3689,2941,
121  929,533,2841,4077,721,2821,2249,2397,2817,245,1913,1997,3121,997,
122  1833,2877,1633,981,2009,941,2449,197,2441,285,1473,2741,3129,909,
123  2801,421,4073,2813,2337,1429,1177,1901,81,1669,2633,2269,129,1141,
124  249,3917,2481,3941,2217,2749,3041,1877,345,2861,1809,3141,2825,
125  157,2881,3637,1465,2829,2161,3365,361,2685,3745,2325,3609,3821,
126  3537,517,3017,2141,1537 };
127  /* System generated locals */
128  integer i__1;
129  /* Local variables */
130  integer i__, i1, i2, i3, i4, it1, it2, it3, it4;
131 #define mm_ref(a_1,a_2) mm[(a_2)*128 + a_1 - 129]
132 
133  --iseed;
134  --x;
135 
136  /* Initialization added by Elias to get rid of compiler warnings. */
137  it1 = it2 = it3 = it4 = 0;
138  /* Function Body */
139 
140  i1 = iseed[1];
141  i2 = iseed[2];
142  i3 = iseed[3];
143  i4 = iseed[4];
144 
145  i__1 = minMACRO(*n,128);
146  for (i__ = 1; i__ <= i__1; ++i__) {
147 
148 /* Multiply the seed by i-th power of the multiplier modulo 2**48 */
149 
150  it4 = i4 * mm_ref(i__, 4);
151  it3 = it4 / 4096;
152  it4 -= it3 << 12;
153  it3 = it3 + i3 * mm_ref(i__, 4) + i4 * mm_ref(i__, 3);
154  it2 = it3 / 4096;
155  it3 -= it2 << 12;
156  it2 = it2 + i2 * mm_ref(i__, 4) + i3 * mm_ref(i__, 3) + i4 * mm_ref(
157  i__, 2);
158  it1 = it2 / 4096;
159  it2 -= it1 << 12;
160  it1 = it1 + i1 * mm_ref(i__, 4) + i2 * mm_ref(i__, 3) + i3 * mm_ref(
161  i__, 2) + i4 * mm_ref(i__, 1);
162  it1 %= 4096;
163 
164 /* Convert 48-bit integer to a real number in the interval (0,1) */
165 
166  x[i__] = ((Treal) it1 + ((Treal) it2 + ((Treal) it3 + (
167  Treal) it4 * 2.44140625e-4) * 2.44140625e-4) *
168  2.44140625e-4) * 2.44140625e-4;
169 /* L10: */
170  }
171 
172 /* Return final value of seed */
173 
174  iseed[1] = it1;
175  iseed[2] = it2;
176  iseed[3] = it3;
177  iseed[4] = it4;
178  return 0;
179 
180 /* End of DLARUV */
181 
182 } /* dlaruv_ */
183 
184 #undef mm_ref
185 
186 
187 #endif
int integer
Definition: template_blas_common.h:38
#define minMACRO(a, b)
Definition: template_blas_common.h:44
#define mm_ref(a_1, a_2)
int dlaruv_(integer *iseed, const integer *n, Treal *x)
Definition: template_lapack_laruv.h:40