1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
|
/* $Id: testBasis.cpp 1662 2011-01-04 17:52:40Z lou $ */
// Copyright (C) 2003, International Business Machines
// Corporation and others. All Rights Reserved.
// This code is licensed under the terms of the Eclipse Public License (EPL).
#include "ClpSimplex.hpp"
#include "CoinHelperFunctions.hpp"
#include <iomanip>
#include <cassert>
int main(int argc, const char *argv[])
{
ClpSimplex model;
int status;
// Keep names
if (argc < 2) {
status = model.readMps("small.mps", true);
} else {
status = model.readMps(argv[1], true);
}
if (status)
exit(10);
/*
This driver turns a problem into all equalities, solves it and
then creates optimal basis.
*/
// copy of original
ClpSimplex model2(model);
// And another
ClpSimplex model3(model);
int originalNumberColumns = model.numberColumns();
int numberRows = model.numberRows();
int * addStarts = new int [numberRows+1];
int * addRow = new int[numberRows];
double * addElement = new double[numberRows];
double * newUpper = new double[numberRows];
double * newLower = new double[numberRows];
double * lower = model2.rowLower();
double * upper = model2.rowUpper();
int iRow;
// Simplest is to change all rhs to zero
// One should skip E rows but this is simpler coding
for (iRow = 0; iRow < numberRows; iRow++) {
newUpper[iRow] = upper[iRow];
upper[iRow] = 0.0;
newLower[iRow] = lower[iRow];
lower[iRow] = 0.0;
addRow[iRow] = iRow;
addElement[iRow] = -1.0;
addStarts[iRow] = iRow;
}
addStarts[numberRows] = numberRows;
model2.addColumns(numberRows, newLower, newUpper, NULL,
addStarts, addRow, addElement);
delete [] addStarts;
delete [] addRow;
delete [] addElement;
delete [] newLower;
delete [] newUpper;
// Modify costs
double * randomArray = new double[numberRows];
for (iRow = 0; iRow < numberRows; iRow++)
randomArray[iRow] = CoinDrand48();
model2.transposeTimes(1.0, randomArray, model2.objective());
delete [] randomArray;
// solve
model2.primal();
// first check okay if solution values back
memcpy(model.primalColumnSolution(), model2.primalColumnSolution(),
originalNumberColumns * sizeof(double));
memcpy(model.primalRowSolution(), model2.primalRowSolution(),
numberRows * sizeof(double));
int iColumn;
for (iColumn = 0; iColumn < originalNumberColumns; iColumn++)
model.setColumnStatus(iColumn, model2.getColumnStatus(iColumn));
for (iRow = 0; iRow < numberRows; iRow++) {
if (model2.getRowStatus(iRow) == ClpSimplex::basic) {
model.setRowStatus(iRow, ClpSimplex::basic);
} else {
model.setRowStatus(iRow, model2.getColumnStatus(iRow + originalNumberColumns));
}
}
model.primal(0);
// and now without solution values
for (iColumn = 0; iColumn < originalNumberColumns; iColumn++)
model3.setColumnStatus(iColumn, model2.getColumnStatus(iColumn));
for (iRow = 0; iRow < numberRows; iRow++)
model3.setRowStatus(iRow, model2.getColumnStatus(iRow + originalNumberColumns));
model3.primal(0);
return 0;
}
|
