c - double* 和 double 到二元运算符&类型的无效操作数

Question

刚开始为类(class)编程和编写 C 代码。我的程序应该从 .txt 文件获取数据，计算，然后将结果打印到 .txt 文件。

我得到:

invalid operands of types double* and double to binary operator&

在 fscanf(therm, "%lf %lf",&temp &con); 行(靠近底部的 for 循环)

/* Preprocessor directives */
#include <stdio.h>
#include <math.h>
#define inputfile "c:\\engr 200\\thermal.txt"
#define outputfile "c:\\engr 200\\results.txt"

/*Main function*/
int main (void)
{

    /*Declare and intialize variables*/
    double temp, sumtemp = 0.0, con, sumcon = 0.0, tem_con, sumtem_con =
        0.0, tsq, sumtsq = 0.0;
    int i, ndata;
    FILE *therm, *res;

    /*Open files*/
    therm = fopen (inputfile, "r");
    res = fopen (outputfile, "w");

    /*Print output headings*/
    printf ("******************************************");
    printf ("\nTEMPERATURE vs THERMAL CONDUCTIVITY");
    printf ("\nby ");
    printf ("\n\nTemp    Conduct    Temp Sqrd    Temp*Conduct");

    /* Verify input file and read control number */
    // NOTE: unmatched 'else' followed, presuming a
    //       test for 'therm'
    if (!therm)
    {
        printf ("\n\n\n\n   ERROR OPENING INPUT FILE.");
        printf ("\n\n   PROGRAM TERMINATED.\n\n\n");
        return 0;
    }
    else
    {
        /* Read control number */
        fscanf (therm, "%i", &ndata);

        /* Compute temp and conductivity data and print results */
        for (i = 1; i <= ndata; i++) {
            fscanf (therm, "%lf %lf", &temp & con);
            sumtemp = sumtemp + temp;
            sumcon = sumcon + con;
            sumtsq = sumtsq + pow (temp, 2);
            sumtem_con = sumtem_con + temp * con;
            printf ("\n%3.0f   %5.1f   %6.1f  %6.1f", sumtemp, sumcon, sumtsq,
                    sumtem_con);
            fprintf (res, "%3.0f   %5.1f   %6.1f  %6.1f", sumtemp, sumcon,
                    sumtsq, sumtem_con);
        }
    }

    /*Close the input file*/
    fclose (therm);
    fclose (res);

    /*Exit the program*/
    return 0;
}

你能帮我诊断这个错误吗？

Answer 1

您错过了两个变量之间的逗号，并且还缺少 if 语句。

fscanf(therm, "%lf %lf", &temp &con);

这应该是

fscanf(therm, "%lf %lf", &temp, &con);

应该有一个 if 语句。

/* Verify input file and read control number */