您好，有人可以帮忙吗，我的 SD 和均值数字非常奇怪，我不知道为什么。我觉得我可能以错误的方式访问数组？有一个结构，但也有一个独立的数组，这是我正在使用的。我的中位数很好，但其他一切都是非常奇怪的输出。
#include<iostream>
#include<fstream>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <climits>
using namespace std;
#define output_bit 1 // change it to 1/0 if you want(don't want to print/output
struct Stock{
char date[10];
double open;
double high;
double low;
double close;
int volume;
double adj_close;
};
//debug tip: pause your program
void pauseIT(){
cout << "Wait, press ENTER to continue,...";
cin.clear(); //clear errors
cin.sync(); //clear the buffer
cin.get(); //wait for a letter
}
void setOutputPrecision(int n){
cout.setf(ios::fixed);
cout.setf(ios::showpoint);
cout.precision(n);
}
double* sortArray(double *a, int size);
int findMaxIndex(const double *a, int size);
void MedianandMean(double * stock, int size, double& stockMedian, double& stockMean);
void standardDeviation(double *stock, int size, double& sum, double& avg, double& sum2, double& stdDev);
int main(int argc, char** argv) {
const int n = 249;
Stock GoogleStock[n]; // a struct array
char filename[100] = "google_stock_.txt";
double *google_stock_adj_close=new double[n];
FILE *fp;
char header[100];
// items since the 2nd line in the file
double open, high, low, close, adj_close;
int volume;
char date[10];
//header information
char date_s[10],open_s[10], high_s[10], low_s[10],
close_s[10], volume_s[10], adj_s[10], adj_close_s[10];
int i=0;
// Read a file
fp=fopen(filename, "r"); //open a file for read
// book keeping: make sure it is not a NULL
if(!fp)
perror("Double-check your input file");
// read the header information (first line)
if(!feof(fp)){
fscanf(fp, "%s %s %s %s %s %s %s %s\n", date_s, open_s,
high_s, low_s, close_s,volume_s, adj_s, adj_close_s);
}
// merge the "adj" and "Close" to "AdjClose"
strcat(adj_s, adj_close_s);
strcpy(adj_close_s, adj_s);
//read the main information from the 2nd line to the file end:
// feof will tell you if the file ends
while(!feof(fp)){
fscanf(fp, "%s %lf %lf %lf %lf %10d %lf\n",
date, &open, &high, &low, &close, &volume, &adj_close);
//copy information to a structure array
strcpy(GoogleStock[i].date, date);
GoogleStock[i].open = open;
GoogleStock[i].high = high;
GoogleStock[i].low = low;
GoogleStock[i].close = close;
GoogleStock[i].volume = volume;
GoogleStock[i].adj_close = adj_close;
//copy the adj close price to an independent array
google_stock_adj_close[i]= adj_close;
i++;
}
fclose(fp); //close your program after finishing reading
cout<<"Finish reading \n"<<endl;
if (output_bit) {
cout<<"The stock information is written in a structure array: \n"<<endl;
pauseIT();
for(int i=0;i<n;i++){
fprintf(stderr, "%s %lf %lf %lf %lf %d %lf\n",
GoogleStock[i].date,
GoogleStock[i].open,
GoogleStock[i].high,
GoogleStock[i].low,
GoogleStock[i].close,
GoogleStock[i].volume,
GoogleStock[i].adj_close);
}
cout<<endl<<endl;
}
if(output_bit){
cout<<"This is the adjusted close price of Google stock"<<endl;
pauseIT();
setOutputPrecision(3);
for(int i=0;i<n;i++)
cout<<google_stock_adj_close[i]<<endl;
}
double stockMedian,stockMean,stdDev,sum,avg,sum2;
stockMedian=stockMean=stdDev=0.0;
MedianandMean((double *) google_stock_adj_close,n, stockMedian, stockMean);
standardDeviation((double *) google_stock_adj_close, n, sum, avg, sum2, stdDev);
cout<<"The stock median = "<<stockMedian<<endl;
cout<<"The stock mean = "<<stockMean<<endl;
cout<<"The stock standard deviation = "<<stdDev<<endl;
delete []google_stock_adj_close;
return 0;
}
int findMaxIndex(const double *a, int size){
int index=0;
double max=a[0];
for (int i=1;i<size;i++){
if (a[i]>max){
max=a[i];
index=i;
}
}
return index;
}
double * sortArray(double *a, int size){
int index;
double *sortedArray=new double[size];
for(int i=0;i<size;i++){
index =findMaxIndex(a, size);
sortedArray[i]=a[index];
a[index]=LONG_MIN;
}
return sortedArray;
}
void MedianandMean(double * stock, int size, double& stockMedian, double& stockMean){
stockMedian=0.0;
double *sorted_stock=sortArray(stock,size);
if(size%2==0)
stockMedian=sorted_stock[(size-1)/2];
else
stockMedian=(sorted_stock[(size-1)/2]+sorted_stock[((size-1)/2)+1])/2;
//Mean
stockMean=0.0;
for(int i=0;i<size;i++)
stockMean=stockMean+stock[i];
stockMean=stockMean/size;
}
void standardDeviation(double *stock, int size, double& sum, double& avg, double& sum2, double& stdDev){
//stanadard deviation
double temp=0.0;
for (int i=0; i<size;i++)
sum=sum+stock[i];
avg=sum/float(size);
for(int i=0; i<size; i++)
sum2 += pow((stock[size]-avg),2);
temp =sum2/(size-1);
stdDev= pow(temp, 0.5);
}