Question

我是编程新手，所以我有一个基本问题。我目前有一个365行的文本文件...一年中每天一行。这些是文件的前四行：

2003 1 1 18 0 -1 36 50 46
2003 1 2 16 3 -1 43 56 52
2003 1 3 19 7 -1 42 56 49
2003 1 4 14 3 -1 42 58 50

我最终必须使用提供给我们的特殊库来绘制这些图，但首先我想将每列的数据放入数组中。这是我的代码的一部分，我试图这样做。

#include "library.h"
#include <iostream>
#include <fstream>
#include <iomanip>

using namespace std;

ifstream in;
int yr[364], mo[364], day[364], windSpeed[364], precip[364], snowDepth[364], minTemp[364], maxTemp[364], avgTemp[364];

void main() {
    make_window(800, 800);
    set_pen_color(color::red);
    set_pen_width(8);

// open file, read in data
    in.open("PORTLAND-OR.TXT");
    if (in.is_open()) {
        // read each column into an array
        for (int i = 0; i < 364; i++) {
            in >> yr[i] >> mo[i] >> day[i] >> windSpeed[i] >> precip[i] >> snowDepth[i] >> minTemp[i] >> maxTemp[i] >> avgTemp[i];
            cout << mo[i] << "    " << day[i] << endl;

        }
        in.close();
    }
    else {
        cout << "error reading file" << endl;
        exit(1);
    }
}

当我尝试打印第二列和第三列（月和日）中的所有值时，它将从3月8日（3月8日）到12月31日（12月31日）开始打印。我需要它从1月1日到12月31日一直打印。有没有理由说前两个月的价值不打印？

Answer 1

下面是一个非常愚蠢的主要程序，它使用您现有的阅读代码读取您的文件并再次打印出来。我已经在代码中嵌入了一个正在运行的注释，其中包含您应该考虑的事项。

基本上，我昨天在loop not displaying all data entries from file

谈论的是这个

#include <iostream>
#include <fstream>

using namespace std; // bad! Avoid doing this in real life.

int yr[364], 
    mo[364], 
    day[364], 
    windSpeed[364], 
    precip[364], 
    snowDepth[364], 
    minTemp[364], 
    maxTemp[364], 
    avgTemp[364]; // bad! define a structure instead


/* Example:
struct stats
{
    int yr; 
    int mo; 
    int day; 
    int windSpeed; 
    int precip; 
    int snowDepth; 
    int minTemp; 
    int maxTemp; 
    int avgTemp;
};

struct stats statistics[364]; // bad! use a std::vector instead

std::vector<stats> statistics; 
*/

int main()
{
    // removed all the windowing stuff.
    ifstream in;
    in.open("PORTLAND-OR.TXT");
    if (in.is_open())
    {
        // read each column into an array
        for (int i = 0; i < 364; i++)
        { // what do you do if the file ends early or contains bad information?
            in >> yr[i] >>
                  mo[i] >>
                  day[i] >>
                  windSpeed[i] >>
                  precip[i] >>
                  snowDepth[i] >>
                  minTemp[i] >>
                  maxTemp[i] >>
                  avgTemp[i];
        }
        in.close();
    }
    else
    {
        cout << "error reading file" << endl;
        return 1;
    }
    // printing out all the stuff that was read 
    for (int i = 0; i < 364; i++)
    {
        cout << yr[i] << "," <<
                mo[i] << "," <<
                day[i] << "," <<
                windSpeed[i] <<  "," <<
                precip[i] <<  "," <<
                snowDepth[i] <<  "," <<
                minTemp[i] <<  "," <<
                maxTemp[i] <<  "," <<
                avgTemp[i] << endl;
    }
}

将文件列读入数组

1 个答案: