Help! C programming...#include #include #define NT double NT f(NT x, NT y) { return x+y; } NT rkstep (NT (*func)(NT, NT), NT x, NT y[], NT h, int n, NT *err[]) { NT k[n], y12[n], y1[n], k12[n]; k[n]=(*func)(x,y[n]); y12[n]=y[n]+k[n]*h/2; k12[n]=(*func)(x,y12[n]); y1[n]=y[n]+k12[n]*h; *err[n]=fabs(k[n]-k12[n])*h/2; return y1[n]; } int main () { int n; NT x, y[n], h, *err[n], result[n]; x=1; y[0]=10; for (n=0;n (more...)

Help! C programming...#include #include #define NT double NT f(NT x, NT y) { return x+y; } NT rkstep (NT (*func)(NT, NT), NT x, NT y[], NT h, int n, NT *err[]) { NT k[n], y12[n], y1[n], k12[n]; k[n]=(*func)(x,y[n]); y12[n]=y[n]+k[n]*h/2; k12[n]=(*func)(x,y12[n]); y1[n]=y[n]+k12[n]*h; *err[n]=fabs(k[n]-k12[n])*h/2; return y1[n]; } int main () { int n; NT x, y[n], h, *err[n], result[n]; x=1; y[0]=10; for (n=0;n (more...)

rkstep(&f,x,y,h,n,&err[n]);试试， 感觉这里面的错误不止这个，你声明数组的时候，怎么用变量来定义数组的大小 NT x, y[n], h, *err[n], result[n];？？？ main function NT k[n], y12[n], y1[n], k12[n]; /?? rkstep function 这编译器是怎么通过的？

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

malloc 和 free 是C 自带的，不用另外连接 library。

rkstep(&f,x,y,h,n,&err[n]);试试， 感觉这里面的错误不止这个，你声明数组的时候，怎么用变量来定义数组的大小 NT x, y[n], h, *err[n], result[n];？？？ main function NT k[n], y12[n], y1[n], k12[n]; /?? rkstep function 这编译器是怎么通过的？