- changed function::diff() to be more tolerant by checking first if the

[ginac.git] / check / differentiation.cpp

diff --git a/check/differentiation.cpp b/check/differentiation.cpp
index 3d49062b82b79b5784d274fe8c288f953aff2581..0d963fed8b0f6d830a56063f71859a9a6786d561 100644 (file)
--- a/check/differentiation.cpp
+++ b/check/differentiation.cpp
@@ -164,6 +164,7 @@ static unsigned differentiation3(void)
     ex e1, e2, e, d;
 
     // construct expression e to be diff'ed:
     ex e1, e2, e, d;
 
     // construct expression e to be diff'ed:

+    e1 = y*pow(x, 2) + a*x + b;

     e2 = exp(e1);
     e = b*pow(e2, 2) + y*e2 + a;
     
     e2 = exp(e1);
     e = b*pow(e2, 2) + y*e2 + a;
     


@@ -191,6 +192,7 @@ static unsigned differentiation4(void)
     ex e1, e2, e, d;
     
     // construct expression e to be diff'ed:
     ex e1, e2, e, d;
     
     // construct expression e to be diff'ed:

+    e1 = y*pow(x, 2) + a*x + b;

     e2 = log(e1);
     e = b*pow(e2, 2) + y*e2 + a;
     
     e2 = log(e1);
     e = b*pow(e2, 2) + y*e2 + a;
     


@@ -232,10 +234,16 @@ static unsigned differentiation5(void)
          pow(y*b+pow(y,2)*x+a,-2)*pow(y,2))*
         pow(1+pow(a*x+b+y*pow(x,2),2)*pow(y*b+pow(y,2)*x+a,-2),-1);
     */
          pow(y*b+pow(y,2)*x+a,-2)*pow(y,2))*
         pow(1+pow(a*x+b+y*pow(x,2),2)*pow(y*b+pow(y,2)*x+a,-2),-1);
     */

+    /*

     d = pow(1+pow(a*x+b+y*pow(x,2),2)*pow(y*b+pow(y,2)*x+a,-2),-1)
         *pow(y*b+pow(y,2)*x+a,-1)*(a+2*y*x)
         +pow(y,2)*(-a*x-b-y*pow(x,2))*
         pow(pow(y*b+pow(y,2)*x+a,2)+pow(a*x+b+y*pow(x,2),2),-1);
     d = pow(1+pow(a*x+b+y*pow(x,2),2)*pow(y*b+pow(y,2)*x+a,-2),-1)
         *pow(y*b+pow(y,2)*x+a,-1)*(a+2*y*x)
         +pow(y,2)*(-a*x-b-y*pow(x,2))*
         pow(pow(y*b+pow(y,2)*x+a,2)+pow(a*x+b+y*pow(x,2),2),-1);

+    */
+    d = pow(y,2)*pow(pow(b+y*pow(x,2)+x*a,2)+pow(y*b+pow(y,2)*x+a,2),-1)*
+        (-b-y*pow(x,2)-x*a)+
+        pow(pow(b+y*pow(x,2)+x*a,2)+pow(y*b+pow(y,2)*x+a,2),-1)*
+        (y*b+pow(y,2)*x+a)*(2*y*x+a);

     result += check_diff(e, x, d);
     
     return result;
     result += check_diff(e, x, d);
     
     return result;