numeric constant

[Jay566]

could anyone help I just started learning c and I couldn't fix this this error in the program

errors are

stat.c:16: error: expected ‘;’, ‘,’ or ‘)’ before numeric constant
stat.c:25: error: expected ‘;’, ‘,’ or ‘)’ before numeric constant

line 16 void pop_arr(double data[], const int sz)
line 25 void print_arr(const double data[], const int sz)

the code

#include <stdio.h>
#define sz 10
 
double read_double(const char* prompt)
{
    double result;
    printf("%s", prompt);
        while(scanf(" %lf", &result) != 1)
        {
            scanf("%*[\n]");
            printf("%s\n", prompt);
        }
    return result;
}
 
void print_arr(const double data[], const int sz)
{
    int i;
    for (i = 0; i < sz; i++)
    {
        printf("%lf\n", data[]);
    }
}
 
void pop_arr(double data[], const int sz)
{
    int i;
    for (i = 0; i < sz; i++)
    {
        data[i] = read_double("Enter a value");
    }
}
 
int main()
{
    double data[sz];
    pop_arr(data, sz);
    print_arr(data, sz);
 
    // return 0;
}

[Banfa]

On line 2 you have #defined sz to 10. This is a text substitution performed by the preprocessor before the compiler runs on all the code so the line void print_arr(const double data[], const int sz) is modified to void print_arr(const double data[], const int 10) by the time the compiler sees it and that produces your error.

You need to be much more careful about the names you give to you #defined symbols and make the much more meaningful so that you don't accidentally get clashes like this with parameter/variable/other symbol names.

[Jay566]

Sorry but I knew this already I dont understand the error message tho. I tried changing the define
to size instead of sz but still doesn't work .

[weaknessforcats]

What the compiler sees is:

void print_arr(const double data[], const int 10)
{ etc...

The "const int 10" is meaningless so the compiler just puts out a generic error message that maybe you have left out some syntax.

You have to decide whether sz ia an int or a 10. It can't be both in C but it could be both in C++ where you are allowed default values.

BTW changing sz to size does work. BUT-- you need to fix an error in print_arr. printf needs to show data[i] rather than data[].

[Jay566]

Thanks for the help guys finally worked it out ..

#include <stdio.h>
#define data_size 10
 
double read_double(const char* prompt)
{
    double result;
    printf("%s", prompt);
        while(scanf(" %lf", &result) != 1)
        {
            scanf("%*[\n]");
            printf("%s\n", prompt);
        }
    return result;
}
 
double sum(const double data[], const int size)
{
    int i;
    double result;
 
    for (i = 0; i < size; ++i)
    {
        result += data[i];
    }
    return result;
}
 
double mean(const double data[], const int size)
{
    return sum(data, size)/ size;
}
 
double max(const double data[], const int size)
{
    int i;
    int max= data[0];
    for (i = 0; i < 10; i++)
    {
      if (data[i] > max)
        {
           max = data[i];
        }
     }
    return max;
}
 
void print_arr(const double data[], const int size)
{
    int i;
    for (i = 0; i < size; i++)
    {
        printf("%lf\n", data[i]);
    }
}
 
void pop_arr(double data[], const int size)
{
    int i;
    for (i = 0; i < size; i++)
    {
        data[i] = read_double("Enter a value");
    }
}
 
int main()
{
    double data[data_size];
    pop_arr(data, data_size);
    print_arr(data, data_size);
    printf("Sum:     %4.2f\n", sum(data, data_size));
    printf("Mean:     %4.2f\n", mean(data, data_size));
    printf("Max:     %4.2f\n", max(data, data_size));
    return 0;
}