A-M baby

Task/Matrix-exponentiation-operator/C/matrix-exponentiation-operator.c

@@ -0,0 +1,184 @@
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef struct squareMtxStruct {
+    int   dim;
+    double *cells;
+    double **m;
+} *SquareMtx;
+
+/* function for initializing row r of a new matrix */
+typedef void (*FillFunc)( double *cells, int r, int dim, void *ff_data);
+
+SquareMtx NewSquareMtx( int dim, FillFunc fillFunc, void *ff_data )
+{
+    SquareMtx sm = malloc(sizeof(struct squareMtxStruct));
+    if (sm) {
+        int rw;
+        sm->dim = dim;
+        sm->cells = malloc(dim*dim * sizeof(double));
+        sm->m = malloc( dim * sizeof(double *));
+        if ((sm->cells != NULL) && (sm->m != NULL)) {
+            for (rw=0; rw<dim; rw++) {
+                sm->m[rw] = sm->cells + dim*rw;
+                fillFunc( sm->m[rw], rw, dim, ff_data );
+            }
+        }
+        else {
+            free(sm->m);
+            free(sm->cells);
+            free(sm);
+            printf("Square Matrix allocation failure\n");
+            return NULL;
+        }
+    }
+    else {
+        printf("Malloc failed for square matrix\n");
+    }
+    return sm;
+}
+
+void ffMatxSquare( double *cells, int rw, int dim, SquareMtx m0 )
+{
+    int col, ix;
+    double sum;
+    double *m0rw = m0->m[rw];
+
+    for (col = 0; col < dim; col++) {
+        sum = 0.0;
+        for (ix=0; ix<dim; ix++)
+            sum += m0rw[ix] * m0->m[ix][col];
+        cells[col] = sum;
+    }
+}
+
+void ffMatxMulply( double *cells, int rw, int dim, SquareMtx mplcnds[] )
+{
+    SquareMtx mleft = mplcnds[0];
+    SquareMtx mrigt = mplcnds[1];
+    double sum;
+    double *m0rw = mleft->m[rw];
+    int col, ix;
+
+    for (col = 0; col < dim; col++) {
+        sum = 0.0;
+        for (ix=0; ix<dim; ix++)
+            sum += m0rw[ix] * mrigt->m[ix][col];
+        cells[col] = sum;
+    }
+}
+
+void MatxMul( SquareMtx mr, SquareMtx left, SquareMtx rigt)
+{
+    int rw;
+    SquareMtx mplcnds[2];
+    mplcnds[0] = left; mplcnds[1] = rigt;
+
+    for (rw = 0; rw < left->dim; rw++)
+        ffMatxMulply( mr->m[rw], rw, left->dim, mplcnds);
+}
+
+void ffIdentity( double *cells, int rw, int dim, void *v )
+{
+    int col;
+    for (col=0; col<dim; col++) cells[col] = 0.0;
+    cells[rw] = 1.0;
+}
+void ffCopy(double *cells, int rw, int dim, SquareMtx m1)
+{
+    int col;
+    for (col=0; col<dim; col++) cells[col] = m1->m[rw][col];
+}
+
+void FreeSquareMtx( SquareMtx m )
+{
+    free(m->m);
+    free(m->cells);
+    free(m);
+}
+
+SquareMtx SquareMtxPow( SquareMtx m0, int exp )
+{
+    SquareMtx v0 = NewSquareMtx(m0->dim, ffIdentity, NULL);
+    SquareMtx v1 = NULL;
+    SquareMtx base0 = NewSquareMtx( m0->dim, ffCopy, m0);
+    SquareMtx base1 = NULL;
+    SquareMtx mplcnds[2], t;
+
+    while (exp) {
+        if (exp % 2) {
+            if (v1)
+                MatxMul( v1, v0, base0);
+            else  {
+                mplcnds[0] = v0; mplcnds[1] = base0;
+                v1 = NewSquareMtx(m0->dim, ffMatxMulply, mplcnds);
+            }
+            {t = v0; v0=v1; v1 = t;}
+        }
+        if (base1)
+            MatxMul( base1, base0, base0);
+        else
+            base1 = NewSquareMtx( m0->dim, ffMatxSquare, base0);
+        t = base0; base0 = base1; base1 = t;
+        exp = exp/2;
+    }
+    if (base0) FreeSquareMtx(base0);
+    if (base1) FreeSquareMtx(base1);
+    if (v1) FreeSquareMtx(v1);
+    return v0;
+}
+
+FILE *fout;
+void SquareMtxPrint( SquareMtx mtx, const char *mn )
+{
+    int rw, col;
+    int d = mtx->dim;
+
+    fprintf(fout, "%s dim:%d =\n", mn, mtx->dim);
+
+    for (rw=0; rw<d; rw++) {
+        fprintf(fout, " |");
+        for(col=0; col<d; col++)
+            fprintf(fout, "%8.5f ",mtx->m[rw][col] );
+        fprintf(fout, " |\n");
+    }
+    fprintf(fout, "\n");
+}
+
+void fillInit( double *cells, int rw, int dim, void *data)
+{
+    double theta = 3.1415926536/6.0;
+    double c1 = cos( theta);
+    double s1 = sin( theta);
+
+    switch(rw) {
+    case 0:
+        cells[0]=c1; cells[1]=s1; cells[2]=0.0;
+        break;
+    case 1:
+        cells[0]=-s1; cells[1]=c1; cells[2]=0;
+        break;
+    case 2:
+        cells[0]=0.0; cells[1]=0.0; cells[2]=1.0;
+        break;
+    }
+}
+
+int main()
+{
+    SquareMtx m0 = NewSquareMtx( 3, fillInit, NULL);
+    SquareMtx m1 = SquareMtxPow( m0, 5);
+    SquareMtx m2 = SquareMtxPow( m0, 9);
+    SquareMtx m3 = SquareMtxPow( m0, 2);
+
+//  fout = stdout;
+    fout = fopen("matrx_exp.txt", "w");
+    SquareMtxPrint(m0, "m0"); FreeSquareMtx(m0);
+    SquareMtxPrint(m1, "m0^5"); FreeSquareMtx(m1);
+    SquareMtxPrint(m2, "m0^9"); FreeSquareMtx(m2);
+    SquareMtxPrint(m3, "m0^2"); FreeSquareMtx(m3);
+    fclose(fout);
+
+    return 0;
+}