- fixed typos

[ginac.git] / ginac / mul.cpp

diff --git a/ginac/mul.cpp b/ginac/mul.cpp
index 8e641caf2ddec551ccfd6f86308649b5690b9d06..3dfe48ebd387bcf8a62671a34a82b1d63c4da310 100644 (file)
--- a/ginac/mul.cpp
+++ b/ginac/mul.cpp
@@ -26,6 +26,7 @@
 #include "mul.h"
 #include "add.h"
 #include "power.h"
+#include "matrix.h"
 #include "archive.h"
 #include "debugmsg.h"
 #include "utils.h"
@@ -143,7 +144,7 @@ void mul::print(const print_context & c, unsigned level) const
                        overall_coeff.bp->print(c, precedence());
                        c.s << "*";
                }
-       
+
                // Print arguments, separated by "*" or "/"
                epvector::const_iterator it = seq.begin(), itend = seq.end();
                while (it != itend) {
@@ -404,6 +405,46 @@ ex mul::evalf(int level) const
        return mul(s,overall_coeff.evalf(level));
 }
 
+ex mul::evalm(void) const
+{
+       // numeric*matrix
+       if (seq.size() == 1 && seq[0].coeff.is_equal(_ex1())
+        && is_ex_of_type(seq[0].rest, matrix))
+               return ex_to_matrix(seq[0].rest).mul(ex_to_numeric(overall_coeff));
+
+       // Evaluate children first, look whether there are any matrices at all
+       // (there can be either no matrices or one matrix; if there were more
+       // than one matrix, it would be a non-commutative product)
+       epvector *s = new epvector;
+       s->reserve(seq.size());
+
+       bool have_matrix = false;
+       epvector::iterator the_matrix;
+
+       epvector::const_iterator it = seq.begin(), itend = seq.end();
+       while (it != itend) {
+               const ex &m = recombine_pair_to_ex(*it).evalm();
+               s->push_back(split_ex_to_pair(m));
+               if (is_ex_of_type(m, matrix)) {
+                       have_matrix = true;
+                       the_matrix = s->end() - 1;
+               }
+               it++;
+       }
+
+       if (have_matrix) {
+
+               // The product contained a matrix. We will multiply all other factors
+               // into that matrix.
+               matrix m = ex_to_matrix(the_matrix->rest);
+               s->erase(the_matrix);
+               ex scalar = (new mul(s, overall_coeff))->setflag(status_flags::dynallocated);
+               return m.mul_scalar(scalar);
+
+       } else
+               return (new mul(s, overall_coeff))->setflag(status_flags::dynallocated);
+}
+
 ex mul::simplify_ncmul(const exvector & v) const
 {
        if (seq.size()==0) {