copy paste 的时候 有问题，再改一下#include #include #define NT double NT f(NT x, NT y) { return x+y; } NT rkstep (NT x, NT y, NT h, NT *err_i) { NT k, y12, y1, k12; k = f(x,y); y12 = y + k*h/2; k12 = f(x, y12); y1 = y + k12*h; *err_i = fabs(k-k12)*h/2; return y1; } int main () { int i = 0; // for loop index NT x = 1; NT h = 1; // what is the value of "h" ? // dynamic sized arrays, (actually these are pointers) NT *y; NT *err; NT *result; int bound = 4; // "bound" is the size of your array x=1; // allocate memory for pointers y = (NT*) malloc(bound*sizeof(NT)); err = (NT*) malloc(bound*sizeof(NT)); result = (NT*) malloc(bound*sizeof(NT)); // ensure memory allocation is successful if(y == NULL || err == NULL || result == NULL) { printf("malloc() error: y, error or result!"); return 0; } y[0]=10; for (i=0; i