3 ms·

> I don't see a problem with simplifying the exponents first. Sure, we call that computer algebra. As soon as you start doing that, you aren't doing automatic

• adamnemecek 7y ago
  You could similarly say that a computer can't calculate x^1000/x^998 because you can't fit it in 32/64 bits.
  • petschge 7y ago
    And computers have a hard time with that. Take the following example code: #include <math.h> #include <stdio.h> #include <stdlib.h> double f(const double x) { return pow(x, 1000) / pow(x, 998); } int main(int argc, char* argv[]) { if(argc != 2) { fprintf(stderr, "Usage: %s x\n", argv[0]); exit(1); } const double x = atof(argv[1]); // demo code without error checking printf("x = %g, f(x) = %g\n", x, f(x)); exit(0); } compile with gcc -Wall -g -o test test.c -lm and run it petschge@localhost:~$ ./test 0 x = 0, f(x) = -nan petschge@localhost:~$ ./test 1 x = 1, f(x) = 1 petschge@localhost:~$ ./test 2 x = 2, f(x) = 4 The fun thing is, when you compile with gcc -Wall -O3 -ffast-math -g -o test2 test.c -lm you actually get petschge@localhost:~$ ./test2 0 x = 0, f(x) = 0
    • adamnemecek 7y ago
      That's exactly what i'm saying.