Hi, Thank you for your answering :) I have worked out this problem. Yes, that is the reason that the exponent 2 of the expression must be defined to integer type. I am sorry that I provided it is double type, 2.0 . However, the error message do not cast light on me clearly enough. by the way, I found the compile result is different between the kdevelop and the console compile command. For example, // test.cpp #include <iostream> #include <ginac/ginac.h> using namespace std; using namespace GiNaC; int main(int argc, char *argv[]) { symbol x("x"); ex exp = sin(x); cout << exp << endl; return EXIT_SUCCESS; }; that is ok when you typed the command: c++ test.cpp -o test -lcln -lginac , the result showed ->sin(x); but on the kdevelop, the compiler will show you the error messages: /usr/local/include/ginac/container.h: In member function `GiNaC::container_storage<C>::STLT GiNaC::container<<anonymous template template parameter> >::evalchildren(int) const [with C = std::vector]': /usr/local/include/ginac/container.h:557: instantiated from `GiNaC::ex GiNaC::container<<anonymous template template parameter> >::eval(int) const [with C = std::vector]' /usr/local/include/ginac/container.h:130: instantiated from here /usr/local/include/ginac/container.h:708: exception handling disabled, use -fexceptions to enable That is same for asin,cos,acos, and so on. I think the error may be parameter type of the sin founction, because you definded the parameter of sin() is numeric type(that is smoothful when given the numeric type to x ). If I definded the x as numeric type, I have not given the ginac symbolic computing performance for trigonometric functions... That is so pity. I hope the symbolic computing performance will include the trigonometric functions. Could you give me some advice? Thanks again. (My computer is PIII 550,RedHat linux9, ginac-1.3.0, gcc-3.0, and the developing tool is kdevelop ) -Qin An ======= 2004-12-22 05:48:17 您在来信中写道：=======
Hi,
I cannot reproduce your findings.
On Mon, 20 Dec 2004, Qin An wrote:
some standard functions do not run smothfully everytime
the function -- expand: when I used it as follow: #include <iostream> #include <ginac/ginac.h> using namespace std; using namespace GiNaC;
main() { ex e = expand(power(x+1,2)); cout << e << endl; } the result given by ginac is: (x+1)^2
You have not declared x. When I do so, the output is 1+x^2+2*x, as it should.
but when I give him the parameters as follows: main() { ex e = expand((x+1)*(x+1)); cout << e << endl; } the result is right: 1.0 + x^2.0 + 2.0*x
I get the same as above. Again, as it should. But with integers, rather than with floating point values.
the difference above is conspicuous, when the above function has been used in other C++ class files that have not the main function.
could anyone give some advice? thanks!
Please provide a self-contained example program, if necessary together with instructions how to compile and invoke it. Please provide the output you obtain and the output you think would be correct. Otherwise nobody will be able to help you.
by the way, my computer is PIII 550, REDHAT Linux 9,gcc is 3.0, and the developing tool is kdevelop.
Please include the version of GiNaC you are using.
Regards -richy. -- Richard B. Kreckel <http://www.ginac.de/~kreckel/>
_______________________________________________ GiNaC-devel mailing list GiNaC-devel@ginac.de http://thep.physik.uni-mainz.de/mailman/listinfo/ginac-devel
= = = = = = = = = = = = = = = = = = = = 致 礼！ Qin An qin.an@163.com 2004-12-22