- input parser recognizes "sqrt()", which is also used in the output

[ginac.git] / ginac / input_parser.yy

diff --git a/ginac/input_parser.yy b/ginac/input_parser.yy
index bbc07647e80d5459f634c9890a2b336d2799e43a..8ba5bf42f75544e19755349be17fea1b29733a46 100644 (file)
--- a/ginac/input_parser.yy
+++ b/ginac/input_parser.yy
@@ -94,8 +94,15 @@ exp  : T_NUMBER              {$$ = $1;}
        | T_LITERAL             {$$ = $1;}
        | T_DIGITS              {$$ = $1;}
        | T_SYMBOL '(' exprseq ')' {
-               unsigned i = function::find_function(ex_to<symbol>($1).get_name(), $3.nops());
-               $$ = function(i, ex_to<exprseq>($3)).eval(1);
+               string n = ex_to<symbol>($1).get_name();
+               if (n == "sqrt") {
+                       if ($3.nops() != 1)
+                               throw (std::runtime_error("too many arguments to sqrt()"));
+                       $$ = sqrt($3.op(0));
+               } else {
+                       unsigned i = function::find_function(n, $3.nops());
+                       $$ = function(i, ex_to<exprseq>($3)).eval(1);
+               }
        }
        | exp T_EQUAL exp       {$$ = $1 == $3;}
        | exp T_NOTEQ exp       {$$ = $1 != $3;}