随笔分类 - 数值算法
摘要：#include <iostream>using namespace std;int nihe(double *x,double *y,int N){ double a0=0; double a1=0; double sum_x_square=0; double sum_x=0; double sum_y=0; double sum_x_y=0; double x_sum_square=0; for (int i=0;i<N;i++) { sum_x_square+=x[i]*x[i]; sum_y+=y[i];...
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摘要：#include <stdio.h>#include <stdlib.h>#include <math.h>#define PI 3.141592653589793238462643383279 //这三十位的PI我小学就会背了void fft_rec(int N,int offset,int delta,double (*x)[2],double (*X)[2],double (*XX)[2]){ int N2=N/2; int k; double cs,sn; int k00,k01,k10,k11; double tmp0,tmp1; ...
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摘要：#include <iostream>using namespace std;int main(){ double a[] ={2,2,2, 3,2,4, 1,3,9}; double b[] = {1,0.5,2.5}; double m =0; int n=3; for (int i = 0; i < n-1; i++) { for (int j = i + 1; j < n; j++) { m = a[j*n+i] / a[i*n+i]; ...
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摘要：#include <iostream>#include <math.h>using namespace std;int main(){ double a[] = { 4, 2, -2, 2, 2, -3, -2, -3, 14 }; double *L = NULL; double *U = NULL; double tmp=0; int n; //矩阵内总数据个数 int s; //矩阵的阶数 ...
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摘要：#include <iostream>#include <malloc.h>#include <stdlib.h>#include <math.h>using namespace std;double *zuigan(double *a,double *b,double *c,double *f,int n) //追赶法求线性方程组{ double *x=NULL; double *p=NULL; double *q=NULL; x=(double*)malloc(sizeof(double)*n); p=(double*)malloc(size
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摘要：#include <iostream>using namespace std;double laglang(double t,double *x,double *y){ double r=0.0; double temp=1.0; for (int k=0;k<5;k++) { temp=1.0; for (int j=0;j<5;j++) { if (j!=k) { temp*=(t-x[j])/(x[k]-x[j]); } ...
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