differencial form package



Hello Gosei,

>  thank you,this is OK.  On my 5.9.3 with gcl it is not trouble but
>  thru 1 is correct program.

In 5.10.0 there is a test to ensure that a list index is not 0.
That test was not in previous versions.
I have modified cartan_new.lisp so the loop is thru 1.

> Would you please test lorentz_example.txt?

Everything works just as shown in lorentz_example.txt, except for
the last example. The last input in lorentz_example.txt is shown as

  fstar_with_clf([x,y,z],[x,y,z],d(h_st(b1*Dx+b22*Dy+b3*Dz)));

and for that i get

  'diff(b3,z,1)*Dx*Dy*Dz+'diff(b1,x,1)*Dx*Dy*Dz

which doesn't match the output shown in lorentz_example.txt, namely

  'diff(b3,z,1)*Dx*Dy*Dz+'diff(b2,y,1)*Dx*Dy*Dz+'diff(b1,x,1)*Dx*Dy*Dz

Is there an error in the input? If I replace b22 with b2 in the input,
then I get the output shown in lorentz_example.txt.

Thanks again for all your work on this topic.

Robert Dodier