diff --git a/MathEval/parser.y b/MathEval/parser.y
new file mode 100644
index 0000000000000000000000000000000000000000..7c3d250b11ac510474b1de58d6b73bf4a6e9cfe5
--- /dev/null
+++ b/MathEval/parser.y
@@ -0,0 +1,119 @@
+%{
+/*
+ * Copyright (C) 1999, 2002, 2003 Free Software Foundation, Inc.
+ *
+ * This file is part of GNU libmatheval
+ *
+ * GNU libmatheval is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * GNU libmatheval is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with program; see the file COPYING. If not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+ * USA.
+ */
+
+/* This file was modified for inclusion in Gmsh */
+
+#include "common.h"
+#include "node.h"
+
+/* Variables used to communicate with code using parser. */
+extern Node* matheval_root; /* Root of tree representation of function. */
+extern int matheval_ok; /* Flag representing success of parsing. */
+
+/* Report parsing error. */
+int yyerror (char *s);
+
+/* Function used to tokenize string representing function (this function
+ is generated by scanner generator). */
+int yylex (void);
+%}
+
+/* Parser semantic values type. */
+%union {
+ Node *node;
+ Record *record;
+}
+
+/* Grammar terminal symbols. */
+%token <node> NUMBER VARIABLE
+%token <record> FUNCTION
+
+/* Grammar non-terminal symbols. */
+%type <node> expression
+
+%left '-' '+'
+%left '*' '/'
+%left NEG
+%left '^'
+
+/* Grammar start non-terminal. */
+%start input
+
+%%
+
+input
+: expression '\n' {
+ matheval_root = $1;
+ yyerrok;
+ return 1;
+}
+;
+
+expression
+: NUMBER {
+ $$ = $1;
+}
+| VARIABLE {
+ $$ = $1;
+}
+| expression '+' expression {
+ /* Create addition binary operator node. */
+ $$ = node_create ('b', '+', $1, $3);
+}
+| expression '-' expression {
+ /* Create subtraction binary operator node. */
+ $$ = node_create ('b', '-', $1, $3);
+}
+| expression '*' expression {
+ /* Create multiplication binary operator node. */
+ $$ = node_create ('b', '*', $1, $3);
+}
+| expression '/' expression {
+ /* Create division binary operator node. */
+ $$ = node_create ('b', '/', $1, $3);
+}
+| '-' expression %prec NEG {
+ /* Create minus unary operator node. */
+ $$ = node_create ('u', '-', $2);
+}
+| expression '^' expression {
+ /* Create exponentiation unary operator node. */
+ $$ = node_create ('b', '^', $1, $3);
+}
+| FUNCTION '(' expression ')' {
+ /* Create function node. */
+ $$ = node_create ('f', $1, $3);
+}
+| '(' expression ')' {
+ $$ = $2;
+}
+;
+
+%%
+
+int yyerror(char* s)
+{
+ /* Indicate parsing error through appropriate flag and stop
+ parsing. */
+ matheval_ok = 0;
+ return 0;
+}
diff --git a/MathEval/scanner.l b/MathEval/scanner.l
new file mode 100644
index 0000000000000000000000000000000000000000..8c6977fd41b83d043d1f58c0cdcd7b3ceacae71c
--- /dev/null
+++ b/MathEval/scanner.l
@@ -0,0 +1,126 @@
+%{
+/*
+ * Copyright (C) 1999, 2002, 2003 Free Software Foundation, Inc.
+ *
+ * This file is part of GNU libmatheval
+ *
+ * GNU libmatheval is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * GNU libmatheval is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with program; see the file COPYING. If not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+ * USA.
+ */
+
+/* This file was modified for inclusion in Gmsh */
+
+#include "common.h"
+#include "node.h"
+#include "parser.h"
+#include "symbol_table.h"
+
+/* Redefine macro to redirect scanner input from string instead of
+ standard input. */
+#define YY_INPUT( buffer, result, max_size ) \
+{ result = input_from_string (buffer, max_size); }
+
+/* Variables used to communicate with code using scanner. */
+extern SymbolTable *matheval_symbol_table; /* Evaluator symbol table. */
+extern char *matheval_input_string; /* String representing function. */
+
+/* Read next max_size character from string into buffer. */
+static int input_from_string (char *buffer, int max_size);
+%}
+
+/* Token definitions. */
+whitespace [\ \t]+
+digit [0-9]
+number ({digit}+|{digit}+"."{digit}*|{digit}*"."{digit}+)([Ee][-+]?{digit}+)?
+function "Exp"|"Log"|"Sqrt"|"Sin"|"Cos"|"Tan"|"Ctan"|"Asin"|"Acos"|"Atan"|"Actan"|"Sinh"|"Cosh"|"Tanh"|"Ctanh"|"Asinh"|"Acosh"|"Atanh"|"Actanh"|"Fabs"
+identifier [a-zA-Z\_][a-zA-Z0-9\_]*
+
+%%
+
+{whitespace}
+
+{number} {
+ /* Create node representing constant with appropriate value. */
+ melval.node = node_create ('c', atof (metext));
+ return NUMBER;
+}
+
+{function} {
+ /* Find symbol table record corresponding to function name. */
+ melval.record = symbol_table_lookup (matheval_symbol_table, metext);
+ return FUNCTION;
+}
+
+{identifier} {
+ Record *record; /* Symbol table record. */
+ /* Inserty variable into symbol table. */
+ record = symbol_table_insert (matheval_symbol_table, metext, 'v');
+ melval.node = node_create ('v', record);
+ return VARIABLE;
+}
+
+"+" {
+ return '+';
+}
+
+"-" {
+ return '-';
+}
+
+"*" {
+ return '*';
+}
+
+"/" {
+ return '/';
+}
+
+"^" {
+ return '^';
+}
+
+"(" {
+ return '(';
+}
+
+")" {
+ return ')';
+}
+
+"\n" {
+ return '\n';
+}
+
+%%
+
+#undef mewrap
+
+int mewrap() {return 1;}
+
+static int input_from_string (char *buffer, int max_size)
+{
+ int count; /* Count of characters to copy from input string to buffer. */
+
+ /* Calculate count of characters to copy. */
+ count = strlen (matheval_input_string);
+ if (count > max_size)
+ count = max_size;
+
+ /* Perform copy operation and update input string. */
+ memcpy(buffer, matheval_input_string, count);
+ matheval_input_string += count;
+
+ return count;
+}
diff --git a/Plugin/Evaluate.cpp b/Plugin/Evaluate.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..336a3c0386754c2c76972b04f98f3f23f02748c8
--- /dev/null
+++ b/Plugin/Evaluate.cpp
@@ -0,0 +1,209 @@
+// $Id: Evaluate.cpp,v 1.1 2004-05-12 03:23:31 geuzaine Exp $
+//
+// Copyright (C) 1997-2004 C. Geuzaine, J.-F. Remacle
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+// USA.
+//
+// Please report all bugs and problems to <gmsh@geuz.org>.
+
+#include "Plugin.h"
+#include "Evaluate.h"
+#include "List.h"
+#include "Views.h"
+#include "Context.h"
+#include "Numeric.h"
+
+#if defined(HAVE_MATH_EVAL)
+#include "matheval.h"
+#endif
+
+extern Context_T CTX;
+
+StringXNumber EvaluateOptions_Number[] = {
+ {GMSH_FULLRC, "TimeStep", NULL, 0.},
+ {GMSH_FULLRC, "iView", NULL, -1.}
+};
+
+StringXString EvaluateOptions_String[] = {
+ {GMSH_FULLRC, "Expression", NULL, "Sin(v) * Sqrt(x^2+y^2)"}
+};
+
+extern "C"
+{
+ GMSH_Plugin *GMSH_RegisterEvaluatePlugin()
+ {
+ return new GMSH_EvaluatePlugin();
+ }
+}
+
+
+GMSH_EvaluatePlugin::GMSH_EvaluatePlugin()
+{
+ ;
+}
+
+void GMSH_EvaluatePlugin::getName(char *name) const
+{
+ strcpy(name, "Evaluate");
+}
+
+void GMSH_EvaluatePlugin::getInfos(char *author, char *copyright,
+ char *help_text) const
+{
+ strcpy(author, "C. Geuzaine (geuz@geuz.org)");
+ strcpy(copyright, "DGR (www.multiphysics.com)");
+ strcpy(help_text,
+ "Plugin(Evaluate) sets the values associated with\n"
+ "the `TimeStep'-th time step in the view `iView'\n"
+ "to the expression `Expression'. In addition to\n"
+ "the usual mathematical functions, `Expression' can\n"
+ "contain the symbols x, y, z and v, which represent\n"
+ "the three spatial coordinates and the value of the\n"
+ "field, respectively.\n"
+ "\n"
+ "Plugin(Evaluate) is executed in-place.\n");
+}
+
+int GMSH_EvaluatePlugin::getNbOptions() const
+{
+ return sizeof(EvaluateOptions_Number) / sizeof(StringXNumber);
+}
+
+StringXNumber *GMSH_EvaluatePlugin::getOption(int iopt)
+{
+ return &EvaluateOptions_Number[iopt];
+}
+
+int GMSH_EvaluatePlugin::getNbOptionsStr() const
+{
+ return sizeof(EvaluateOptions_String) / sizeof(StringXString);
+}
+
+StringXString *GMSH_EvaluatePlugin::getOptionStr(int iopt)
+{
+ return &EvaluateOptions_String[iopt];
+}
+
+void GMSH_EvaluatePlugin::catchErrorMessage(char *errorMessage) const
+{
+ strcpy(errorMessage, "Evaluate failed...");
+}
+
+static void evaluateList(Post_View * v, List_T * list, int nbElm,
+ int nbNod, int timeStep, char *expression)
+{
+#if !defined(HAVE_MATH_EVAL)
+
+ Msg(GERROR, "MathEval is not compiled in this version of Gmsh");
+
+#else
+
+ double *x, *y, *z, *val;
+ int nb, i, j;
+
+ if(!nbElm)
+ return;
+
+ v->Changed = 1;
+
+ if(timeStep < 0 || timeStep > v->NbTimeStep - 1){
+ Msg(WARNING, "Invalid TimeStep (%d) in View[%d]: choosing TimeStep 0",
+ timeStep, v->Index);
+ timeStep = 0;
+ }
+
+ void *f = evaluator_create(expression);
+
+ if(!f){
+ Msg(GERROR, "Invalid expression '%s'", expression);
+ return;
+ }
+
+ double min = VAL_INF;
+ double max = -VAL_INF;
+
+ nb = List_Nbr(list) / nbElm;
+ for(i = 0; i < List_Nbr(list); i += nb) {
+ x = (double *)List_Pointer_Fast(list, i);
+ y = (double *)List_Pointer_Fast(list, i + nbNod);
+ z = (double *)List_Pointer_Fast(list, i + 2 * nbNod);
+ val = (double *)List_Pointer_Fast(list, i + 3 * nbNod);
+ for(j = 0; j < nbNod; j++) {
+
+ double xx = x[j];
+ double yy = y[j];
+ double zz = z[j];
+ double vv = val[nbNod * timeStep + j];
+
+ char *names[] = { "x", "y" , "z", "v" };
+ double values[] = { xx , yy, zz, vv };
+ double res = evaluator_evaluate(f, sizeof(names)/sizeof(names[0]), names, values);
+
+ val[nbNod * timeStep + j] = res;
+ if(res < min) min = res;
+ if(res > max) max = res;
+ }
+ }
+
+ evaluator_destroy(f);
+
+ v->TimeStepMin[timeStep] = min;
+ v->TimeStepMax[timeStep] = max;
+ v->Min = v->TimeStepMin[0];
+ v->Max = v->TimeStepMax[0];
+ for(int i = 1; i < v->NbTimeStep; i++){
+ if(v->TimeStepMin[i] < v->Min) v->Min = v->TimeStepMin[i];
+ if(v->TimeStepMax[i] > v->Max) v->Max = v->TimeStepMax[i];
+ }
+
+#endif
+}
+
+static void evaluate(Post_View * v, int timeStep, char *expression)
+{
+ evaluateList(v, v->SP, v->NbSP, 1, timeStep, expression);
+ evaluateList(v, v->SL, v->NbSL, 2, timeStep, expression);
+ evaluateList(v, v->ST, v->NbST, 3, timeStep, expression);
+ evaluateList(v, v->SQ, v->NbSQ, 4, timeStep, expression);
+ evaluateList(v, v->SS, v->NbSS, 4, timeStep, expression);
+ evaluateList(v, v->SH, v->NbSH, 8, timeStep, expression);
+ evaluateList(v, v->SI, v->NbSI, 6, timeStep, expression);
+ evaluateList(v, v->SY, v->NbSY, 5, timeStep, expression);
+}
+
+Post_View *GMSH_EvaluatePlugin::execute(Post_View * v)
+{
+ Post_View *vv;
+
+ int timeStep = (int)EvaluateOptions_Number[0].def;
+ int iView = (int)EvaluateOptions_Number[1].def;
+ char *expr = EvaluateOptions_String[0].def;
+
+ if(v && iView < 0)
+ vv = v;
+ else {
+ if(!v && iView < 0)
+ iView = 0;
+ if(!(vv = (Post_View *) List_Pointer_Test(CTX.post.list, iView))) {
+ Msg(WARNING, "View[%d] does not exist", iView);
+ return 0;
+ }
+ }
+
+ evaluate(vv, timeStep, expr);
+ return vv;
+}
+
diff --git a/Plugin/Evaluate.h b/Plugin/Evaluate.h
new file mode 100644
index 0000000000000000000000000000000000000000..73564af9477962cd49f8b5c5ba5afd387e517571
--- /dev/null
+++ b/Plugin/Evaluate.h
@@ -0,0 +1,44 @@
+#ifndef _EVALUATE_H_
+#define _EVALUATE_H
+
+// Copyright (C) 1997-2004 C. Geuzaine, J.-F. Remacle
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+// USA.
+//
+// Please report all bugs and problems to <gmsh@geuz.org>.
+
+#include "Plugin.h"
+
+extern "C"
+{
+ GMSH_Plugin *GMSH_RegisterEvaluatePlugin();
+}
+
+class GMSH_EvaluatePlugin : public GMSH_Post_Plugin
+{
+public:
+ GMSH_EvaluatePlugin();
+ void getName(char *name) const;
+ void getInfos(char *author, char *copyright, char *helpText) const;
+ void catchErrorMessage(char *errorMessage) const;
+ int getNbOptions() const;
+ StringXNumber* getOption(int iopt);
+ int getNbOptionsStr() const;
+ StringXString* getOptionStr(int iopt);
+ Post_View *execute(Post_View *);
+};
+
+#endif