c语言曲线拟合（C language curve fitting）.docVIP

c语言曲线拟合（C language curve fitting） # includes stdio.h # includes stdlib.h # includes malloc.h # includes math.h smooth (double * double * double *, int, int) double, double, double *); void main () { int i, n, m; double * x * y *, dt1, dt2, dt3, b; n = 20; m = 6; b = 0; / * 分别为x, y, a分配存贮空间 * / x = (double *) calloc (n, sizeof (double)); if (x = = null) { printf (内存分配失败 \ n); exit (0); } y = (double *) calloc (n, sizeof (double)); if (y = = null) { printf (内存分配失败 \ n); exit (0); } a = (double *) calloc (n, sizeof (double)); if (a = = null) { printf (内存分配失败 \ n); exit (0); } for (i = 1, the = n; i + +) { x [- 1] = b + (- 1) * 0.1; / * 每隔0.1取一个点, 这样连续取n个点 * / y [- 1] = x (i - 1) - exp (- x [- 1]). / / y [- 1] = x [- 1] * x [- 1] * x [- 1]. / / y [- 1] = x [- 1]. / * 计算x [- 1] 点对应的y值作为拟合已知值 * / } smooth (x, y, a, n, m, dt1, dt2, dt3 调用拟合函数); / * * / for (i = 1, the = m; i + +) printf ([% d] =%.10f \ n, (1), [- 1]). printf (拟合多项式与数据点偏差的平方和为: \ n); printf (%.10e \ n, dt1); printf (拟合多项式与数据点偏差的绝对值之和为: \ n); printf (%.10e \ n, dt2); printf (拟合多项式与数据点偏差的绝对值最大值为: \ n); printf (%.10e \ n, dt3); free (x); / * 释放存储空间 * / free (y); / * 释放存储空间 * / free (a); / * 释放存储空间 * / } smooth (double * x, double * y, double * a, int n, int m, double * dt1, double * dt2, double * dt3) / / / / double * x; / * 实型一维数组, 输入参数, 存放节点的xi值 * / / / / / double * y; / * 实型一维数组, 输入参数, 存放节点的yi值 * / / / / / double * a; / * 双精度实型一维数组, 长度为m.返回m一1次拟合多项式的m个系数 * / / / / / int n; / * 整型变量, 输入参数, 给定数据点的个数 * / / / / / int (m); / * 整型变量, 输入参数, 拟合多项式的项数 * / / / / / double * dt1; / * 实型变量, 输出参数, 拟合多项式与数据点偏差的平方和 * / / / / / double * dt2; / * 实型变量, 输出参数, 拟合多项式与数据点偏差的绝对值之和 * / / / / / double * dt3; / * 实型变量, 输出参数, 拟合多项式与数据点偏差的绝对值最大值 * / { int i, j, k; double * * * s, t, b, z, p, c, d1, d2, g, q, dt; / * 分别为s, t, b分配存贮空间 * / s = (double *) calloc (n, sizeof (double)); if (p = = null) { printf (内存分配失败 \ n); exit (0); } t = (double *) calloc (n, sizeof (double)); if (t = = null) { printf (内存分配失败 \ n); exit (0);