fixed: nml_mat_concath and nml_mat_concath_va functions

examples/concatenate_matrices.c

@@ -0,0 +1,33 @@
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "lib/nml.h"
+
+int main(int argc, char *argv[]) {
+  nml_mat *I = nml_mat_id(3);
+  nml_mat *Ix2 = nml_mat_scalarmult(I, 2.0);
+  // Concatenate using a pointer
+  nml_mat **ms = malloc(sizeof(*ms) * 2);
+  ms[0] = I;
+  ms[1] = Ix2;
+  nml_mat *concats1 = nml_mat_concath(2, ms);
+  //Concatenates using variable arguments list
+  nml_mat *concats2 = nml_mat_concath_va(3, I, Ix2, I);
+
+  printf("I=\n");
+  nml_mat_print(I);
+  printf("Ix2=\n");
+  nml_mat_print(Ix2);
+  printf("concats1=\n");
+  nml_mat_print(concats1);
+  printf("concats2=\n");
+  nml_mat_print(concats2);
+
+  free(ms);
+  nml_mat_free(I);
+  nml_mat_free(Ix2);
+  nml_mat_free(concats1);
+  nml_mat_free(concats2);
+
+  return 0;
+}

nml.c

@@ -447,71 +447,65 @@ int nml_mat_swapcols_r(nml_mat *m, unsigned int col1, unsigned int col2) {
   return 1;
 }
 
-nml_mat *nml_mat_concath(unsigned int mnun, nml_mat **matrices) {
-  return NULL;
-}
-
-// Concatenates a variable number of matrices into one
-// The concentation is done horizontally this means the matrices need to have
-// the same number of rows, while the number of columns is allowed to
-// be variable
-nml_mat *nml_mat_concath_va(unsigned int mnum, ...) {
+nml_mat *nml_mat_concath(unsigned int mnum, nml_mat **marr) {
   if (0==mnum) {
     return NULL;
   }
-  va_list argp;
-  va_start(argp, mnum);
-  nml_mat * fm = va_arg(argp, nml_mat*);
   if (1==mnum) {
     // We just return the one matrix supplied as the first param
     // no need for additional logic
-    va_end(argp);
-    return nml_mat_cp(fm);
+    return nml_mat_cp(marr[0]);
   }
   // We compute to see if the matrices have the same number of rows
   // We fillup the array containing the matrices from the varags
   // We calculate the total number of columns to know how to allocate memory
   // for the resulting matrix]
-  int i,j,k,jk,offset;
+  int i,j,k,offset;
   unsigned int lrow, ncols;
-  nml_mat **marr;
-  marr = malloc(sizeof(*marr) * mnum);
-  marr[0] = fm;
-  lrow = fm->num_rows;
-  ncols = fm->num_cols;
+  lrow = marr[0]->num_rows;
+  ncols = marr[0]->num_cols;
   for(k = 1; k < mnum; k++) {
-    marr[k] = va_arg(argp, nml_mat*);
     if (lrow!=marr[k]->num_rows) {
       NML_FERROR(CANNOT_CONCATENATE_H, lrow, marr[k]->num_rows);
-      free(marr);
       return NULL;
     }
     ncols+=marr[k]->num_cols;
   }
-  va_end(argp);
-
   // At this point we know how the resulting matrix looks like,
   // we allocate memory for it accordingly
   nml_mat *r = nml_mat_new(lrow, ncols);
-  nml_mat_print(r);
   for(i = 0; i < r->num_rows; i++) {
     k = 0;
     offset = 0;
     for(j = 0; j < r->num_cols; j++) {
-      jk = j - offset;
       // If the column index of marr[k] overflows
       // We jump to the next matrix in the array
-      if (jk >= marr[k]->num_cols) {
-        offset = marr[k]->num_cols;
+      if (j-offset == marr[k]->num_cols) {
+        offset += marr[k]->num_cols;
         k++;
       }
-      r->data[i][j] = marr[k]->data[i][jk];
+      r->data[i][j] = marr[k]->data[i][j - offset];
     }
   }
-  free(marr);
   return r;
 }
 
+// Concatenates a variable number of matrices into one
+// The concentation is done horizontally this means the matrices need to have
+// the same number of rows, while the number of columns is allowed to
+// be variable
+nml_mat *nml_mat_concath_va(unsigned int mnum, ...) {
+  nml_mat **marr = malloc(sizeof(*marr) * mnum);
+  va_list argp;
+  va_start(argp, mnum);
+  int k;
+  for(k = 0; k < mnum; k++) {
+    marr[k] = va_arg(argp, nml_mat*);
+  }
+  va_end(argp);
+  return nml_mat_concath(mnum, marr);
+}
+
 // Concatenates a variable number of matrices into one.
 // The concentation is done vertically this means the matrices need to have
 // the same number of columns, while the number of rows is allowed to