int main(void)
{
float d,**a,**al,*b,*x;
unsigned long i,j,*indx;
long idum=(-1);
a=matrix(1,7,1,4);
x=vector(1,7);
b=vector(1,7);
al=matrix(1,7,1,2);
indx=lvector(1,7);
for (i=1;i<=7;i++) {
x[i]=ran1(&idum);
for (j=1;j<=4;j++) {
a[i][j]=ran1(&idum);
}
}
banmul(a,7,2,1,x,b);
for (i=1;i<=7;i++) printf("%ld %12.6f %12.6f\n",i,b[i],x[i]);
bandec(a,7,2,1,al,indx,&d);
banbks(a,7,2,1,al,indx,b);
for (i=1;i<=7;i++) printf("%ld %12.6f %12.6f\n",i,b[i],x[i]);
free_lvector(indx,1,7);
free_matrix(al,1,7,1,2);
free_vector(b,1,7);
free_vector(x,1,7);
free_matrix(a,1,7,1,4);
return 0;
}
int main(void)
{
unsigned long i,j,k;
float **a,**aa,*ax,*b,*x;
a=matrix(1,NP,1,MP);
aa=matrix(1,NP,1,NP);
ax=vector(1,NP);
b=vector(1,NP);
x=vector(1,NP);
for (i=1;i<=M1;i++) for (j=1;j<=NP;j++) a[j][i]=10.0*j+i;
/* Lower band */
for (i=1;i<=NP;i++) a[i][M1+1]=i;
/* Diagonal */
for (i=1;i<=M2;i++) for (j=1;j<=NP;j++) a[j][M1+1+i]=0.1*j+i;
/* Upper band */
for (i=1;i<=NP;i++) {
for (j=1;j<=NP;j++) {
k=i-M1-1;
if (j>=LMAX(1,1+k) && j<=LMIN(M1+M2+1+k,NP))
aa[i][j]=a[i][j-k];
else aa[i][j]=0.0;
}
}
for (i=1;i<=NP;i++) x[i]=i/10.0;
banmul(a,NP,M1,M2,x,b);
for (i=1;i<=NP;i++) {
for (ax[i]=0.0,j=1;j<=NP;j++) ax[i] += aa[i][j]*x[j];
}
printf("\tReference vector\tbanmul vector\n");
for (i=1;i<=NP;i++) printf("\t%12.4f\t%12.4f\n",ax[i],b[i]);
free_vector(x,1,NP);
free_vector(b,1,NP);
free_vector(ax,1,NP);
free_matrix(aa,1,NP,1,NP);
free_matrix(a,1,NP,1,MP);
return 0;
}
int main()
{
int i, j;
VecDoub x(7), b(7);
MatDoub a(7, 4);
a[0][0] = 0.0000000; // arbitrary: not used
a[0][1] = 0.0000000; // arbitrary: not used
a[0][2] = 0.5297000;
a[0][3] = 0.9304360;
a[1][0] = 0.0000000; // arbitrary: not used
a[1][1] = 0.0668422;
a[1][2] = 0.7226600;
a[1][3] = 0.6711490;
a[2][0] = 0.6316350;
a[2][1] = 0.8847070;
a[2][2] = 0.5194160;
a[2][3] = 0.6515190;
a[3][0] = 0.2624530;
a[3][1] = 0.7621980;
a[3][2] = 0.7533560;
a[3][3] = 0.9092080;
a[4][0] = 0.2727100;
a[4][1] = 0.8976560;
a[4][2] = 0.2749070;
a[4][3] = 0.5162920;
a[5][0] = 0.2470390;
a[5][1] = 0.4865170;
a[5][2] = 0.8461670;
a[5][3] = 0.8309650;
a[6][0] = 0.9910370;
a[6][1] = 0.6792960;
a[6][2] = 0.7664950;
a[6][3] = 0.0000000; // arbitrary: not used
x[0] = 0.4159990;
x[1] = 0.3835020;
x[2] = 0.3834160;
x[3] = 0.2377740;
x[4] = 0.0726859;
x[5] = 0.3592650;
x[6] = 0.0345721;
cout << "Banded matrix [a]:" << endl;
cout << fixed << setprecision(7);
for (i = 0; i < a.nrows(); i++) {
for (j = 0; j < a.ncols(); j++) {
cout << setw(12) << a[i][j];
}
cout << endl;
}
cout << endl;
cout << "Vector [x]:" << endl;
for (i = 0; i < x.size(); i++) {
cout << setw(18) << x[i] << endl;
}
cout << endl;
// multiply a times x, giving b
banmul(a, 2, 1, x, b);
cout << "After multiplying [a] times [x] this is [b]:" << endl;
for (i = 0; i < b.size(); i++) {
cout << setw(18) << b[i] << endl;
}
cout << endl;
//
// First, save original value of x
//
VecDoub xsave(x);
//
// The constructor does the decomposition
//
Bandec banded(a, 2, 1);
//
// Now solve for x
//
banded.solve(b, x);
cout << "After solving [a] times [x] = [b] with bandec.solve():" << endl;
cout << " Original Solved" << endl
<< " x x" << endl;
for (i = 0; i < x.size(); i++) {
cout << setw(12) << xsave[i] << setw(12) << x[i] << endl;
}
return 0;
}
