Added .Print() function that outputs matrix in a row col val format

SpMat.h

@@ -21,6 +21,8 @@
 #define SpMat_h
 
 #include <vector>
+#include <fstream>
+#include <iomanip>
 #include <boost/shared_ptr.hpp>
 #include "newmat.h"
 #include "cg.h"
@@ -97,6 +99,12 @@ public:
   unsigned int NZ() const {return(_nz);}
 
   NEWMAT::ReturnMatrix AsNEWMAT() const;
+  void Print(const std::string&  fname,
+             unsigned int        precision) const;
+  void Print(const std::string&  fname) const {Print(fname,8);}
+  void Print(unsigned int        precision) const {Print(std::string(""),precision);}
+  void Print() const {Print(8);}
+
 
   T Peek(unsigned int r, unsigned int c) const;
   T operator()(unsigned int r, unsigned int c) const {return(Peek(r,c));}    // Read-only
@@ -373,6 +381,43 @@ NEWMAT::ReturnMatrix SpMat<T>::AsNEWMAT() const
   return(M);
 }
 
+/////////////////////////////////////////////////////////////////////
+//
+// Prints matrix in a row col val format that is useful for
+// exporting it to Matlab (use Matlab function spconvert).
+//
+/////////////////////////////////////////////////////////////////////
+
+template<class T>
+void SpMat<T>::Print(const std::string&  fname,
+                     unsigned int        precision) const
+{
+  ostream  *sptr=0;
+
+  if (!fname.length()) {
+    sptr = &cout;
+  }
+  else {
+    try {
+      sptr = new ofstream(fname.c_str());
+    }
+    catch(...) {
+      std::string  errmsg("BFMatrix::print: Failed to write to file " + fname);
+      throw SpMatException(errmsg);
+    }
+  }
+  (*sptr) << setprecision(precision);
+
+  for (unsigned int c=0; c<_n; c++) {
+    for (unsigned int i=0; i<_ri[c].size(); i++) {
+      if (_val[c][i]) (*sptr) << _ri[c][i]+1 << "  " << c+1 << "  " << _val[c][i] << endl;
+    }
+  }
+  (*sptr) << _m << "  " << _n << "  " << 0 << endl;
+  
+  if (fname.length()) delete sptr;
+}
+
 /////////////////////////////////////////////////////////////////////
 //
 // Solves for x in expression b=(*this)*x. Uses the IML++ templates