*** empty log message ***

Cantera/clib/src/ctfunc.cpp

@@ -56,6 +56,9 @@ extern "C" {
             else if (type == SumFuncType) {
                 r = new Func1Sum(*_func(n), *_func(m));
             }
+            else if (type == DiffFuncType) {
+                r = new Func1Diff(*_func(n), *_func(m));
+            }
             else if (type == ProdFuncType) {
                 r = new Func1Product(*_func(n), *_func(m));
             }

Cantera/matlab/cantera/@Func/Func.m

@@ -0,0 +1,41 @@
+function x = Func(typ, n, p)
+%
+if ~isa(typ, 'char')
+  error('Function type must be a string')
+end
+
+x.f1 = 0;
+x.f2 = 0;
+x.coeffs = 0;
+
+itype = -1;
+if strcmp(typ, 'polynomial')
+  itype = 2;
+elseif strcmp(typ,'fourier')
+  itype = 1;
+elseif strcmp(typ,'arrhenius')
+  itype = 3;
+end
+
+if itype > 0
+  x.coeffs = p;
+  x.index = funcmethods(0,itype,n,p);  
+else
+  if strcmp(typ,'sum')
+    itype = 20;
+  elseif strcmp(typ,'diff')
+    itype = 25;    
+  elseif strcmp(typ,'prod')
+    itype = 30;
+  elseif strcmp(typ,'ratio')
+    itype = 40;
+  end
+  x.f1 = n;
+  x.f2 = p;
+  x.index = funcmethods(0,itype,n.index,p.index);
+end
+
+x.typ = typ;
+x = class(x,'Func');
+
+

Cantera/matlab/cantera/polynom.m

@@ -0,0 +1,12 @@
+function poly = polynom(coeffs)
+% POLY - create a polynomial Func instance
+%   
+[n m] = size(coeffs);
+if n == 1
+  poly = Func('polynomial',m - 1,coeffs)
+elseif m == 1
+  poly = Func('polynomial',n - 1,coeffs)
+else
+  error('wrong shape for coefficient array')
+end
+

Cantera/src/Func1.h

@@ -24,6 +24,7 @@ namespace Cantera {
     const int PolyFuncType = 2;
     const int ArrheniusFuncType = 3;
     const int SumFuncType = 20;
+    const int DiffFuncType = 25;
     const int ProdFuncType = 30;
     const int RatioFuncType = 40;
  
@@ -65,6 +66,23 @@ namespace Cantera {
             return r;
         }
 
+//         virtual string show(doublereal t) {
+//             int n;
+//             string s = "";
+//             doublereal r = m_c[m_n-1];
+//             for (n = m_n-1; n >= 0; n--) {
+//                 s += fp2str(m_c[n]);
+//                 if (n > 0) s += "*x";
+//                 if (n > 1) s += "^"+int2str(n);
+//                 if (n > 0) {
+//                     if (m_c[n] < 0.0) s += " - ";
+//                     else 
+//                 r *= t;
+//                 r += m_c[m_n - n - 1];
+//             }
+//             return r;
+//         }            
+
     protected:
         int m_n;
         vector_fp m_c;
@@ -159,6 +177,26 @@ namespace Cantera {
     private:
     };
 
+
+    /**
+     * Difference of two functions.
+     */
+    class Func1Diff : public Func1 {
+    public:
+        Func1Diff(Func1& f1, Func1& f2) {
+            m_f1 = &f1;
+            m_f2 = &f2;
+        }
+        virtual ~Func1Diff() {}
+        virtual doublereal eval(doublereal t) {
+            return m_f1->eval(t) - m_f2->eval(t);
+        }
+    protected:
+        Func1 *m_f1, *m_f2;
+    private:
+    };
+
+
     /**
      * Product of two functions.
      */
@@ -177,6 +215,7 @@ namespace Cantera {
     private:
     };
 
+
     /**
      * Ratio of two functions.
      */