Question

我对C编码很陌生，我设计了一个程序，只要用户输入1,2或3就执行某项任务。我有一个80 X值的数据集，对应80 Y值，首先我需要至;找到最小/最大Y值并将其打印到具有相应X值的文件中，对数据文件进行数值积分，然后查找值的均值/标准偏差。基本上我生成的代码将运行程序，但是当输入1,2或3时，它将不会运行任何函数，并将要求另一个值。

就像我说的，我是新手，所以我知道我不会第一次得到它。

#include <Math.h>
#include <stdio.h>
const int X = 1001; // will be used to define number of rows in array
const int Y = 2;    // equally used to define columns

void writeTwoToFile(int answer1, int answer2) {
    FILE* answers;
    answers = fopen("answer.txt", "w");
    fprintf(answers, "The first answer is: %d\n The second answer is: %d\n",
            answer1, answer2);
}
void writeToFile(int answer) {
    FILE* answers;
    answers = fopen("answer.txt", "w");
    fprintf(answers, "The first answer is: %d\n", answer);
}

void max(int dataArray[X][Y]) {
    int col = 1;
    int smallest = 0;
    int largest = 0;
    for (int i = 0; i < 1000; i++) {
        if (dataArray[col][i] > largest) {
            largest = dataArray[col][i];
        } else if (dataArray[col][i] < smallest) {
            smallest = dataArray[col][i];
        }
    }

    writeTwoToFile(smallest, largest);
}

void integrate(int dataArray[X][Y]) {
    int answer = 0;
    for (int i = 0; i < 80; i++) {
        if (i == 0 || i == 79) {
            answer += dataArray[1][i];
        } else if (i % 2 == 1) { //% is a modulo function, does a division and
            returns the remainder,
                easy way of alternating numbers-- answer += dataArray[1][i] * 2;
        } else {
            answer += dataArray[1][i] * 4;
        }
    }
    answer / 12;
    writeToFile(answer);
}

void mean(int dataArray[X][Y]) {
    int mean = 0;
    int stdDeviation = 0;

    for (int i = 0; i < 1000; i++) {
        mean += dataArray[1][i];
    }
    mean / 80;

    for (int j = 0; j < 1000; j++) {
        stdDeviation += pow(dataArray[1][j] - mean, 2);
    }
    stdDeviation / 79;
    sqrt(stdDeviation);

    writeTwoToFile(mean, stdDeviation);
}

int main() {

    int loop = 0;        // act as a loop counter
    int user;            // to collect user input
    int dataArray[X][Y]; // array data is to be stored in

    // Open and read file
    FILE* data;
    data = fopen("data.dat", "r");

    // Read file in to 2D array, 2-1000 matrix essentially
    for (int i = 0; i < 2; i++) {
        for (int j = 0; j < 1000; j++) {
            fscanf(data, "%1d", &dataArray[j][i]);
        }
    }

    printf("Welcome to this calculator, please input one of the following "
           "numbers\n");
    printf("1- Find maximum and minimum\n");
    printf("2- Find definite integral\n");
    printf("3- Calculate the mean and standard deviation\n");

    printf("\n");

    while (loop == 0) {
        printf("Please input the number you want to manipulate\n");
        scanf("%d", &user); // takes user input
        if (user == 1) {
            max(dataArray);
        }

        else if (user == 2) {
            integrate(dataArray);
        }

        else if (user == 3) {
            mean(dataArray);
        }

        else {
            printf("Please enter a valid number");
        }
    }
}

感谢您的任何帮助。

Answer 1

你有一个无限循环。

代码行：

while(loop==0)

主方法中的

将始终评估为true，因为您永远不会增加变量loop。

您应该使用for循环，或在每个输入案例中增加loop。

程序将运行while循环，但不会运行该函数

1 个答案: