pass pointer value to a variable

Question

i'm trying to read values from a txt file. the following code works well, but it only print the values to the standard output, i don't know how to store those values in a variable. Thankyou in advance.

char *value = NULL;
double Training[401], Test[50];
int i=0;
size_t line_buf_size = 0; 
while(i<4)
        {
            getline(&value, &line_buf_size, in_file);
            fscanf(in_file,"%s%*[^\n]",value);
            printf("value %s \n",value);
            Training[i]=(double)value; // error : pointer value used where a floating point value was expected
            //printf(" training %d i %d \n",Training[i], i);
            i++;
        }

What do you mean, "I don't know how to store those values in a variable". It's in `Training`, right? — Fiddling Bits, Nov 20 '20 at 21:40
@VladfromMoscow you mean like this : char line = getline(&value, &line_buf_size, in_file); ? — ayloul, Nov 20 '20 at 21:44
`Training[i]` is a `double` whereas value is a `char*` Can't cast like you are trying to do — edtheprogrammerguy, Nov 20 '20 at 21:48
@edtheprogrammerguy getline() takes pointer and not a variable, i already try that. — ayloul, Nov 20 '20 at 21:49

score 0 · Accepted Answer · answered Nov 20 '20 at 21:52

0

I think the problem you are facing is storing your "value" variable (type: char *) into "Training[i]" (type: double).

You need to convert from char * to double: https://stackoverflow.com/a/10075336/7440867 .

answered Nov 20 '20 at 21:52

David Rosu

39
4

so, is there a way to store the value of the pointer into a variable? – ayloul Nov 20 '20 at 21:59
you can try: `sscanf(value, "%lf", &Training[i]);` – David Rosu Nov 20 '20 at 22:08

pass pointer value to a variable

1 Answers1