reading a columns input data file

I need to read a 3 column input data file and to select (for further calculations) just the first 2 columns...

The problem I have is that when I try to "printf" these data, the program crushes, so I'm not be able to check if my program actually reads corectly the input file...


2.5000000000E+1 1.6285272837E+0 1.2494180202E+0
2.5018749237E+1 1.3162814379E+0 1.9428113699E+0
2.5037498474E+1 1.2828449011E+0 2.7128908634E+0
2.5056249619E+1 1.5575599670E+0 2.9970877171E+0
2.5074998856E+1 1.9759304523E+0 2.5490462780E+0
2.5093750000E+1 2.2521975040E+0 1.6395831108E+0
2.5112499237E+1 2.1530494690E+0 9.4248563051E-1
2.5131248474E+1 1.7716845274E+0 1.0123537779E+0
2.5149999619E+1 1.4909162521E+0 1.7716845274E+0


TO be more, clear, in the first part of my program I read the file line by line (I look for '\n' delimiters), so finally I get the number of lines of the input files... This works fine!
I get lets say, count=373, "count" being the parameter i used for the number of lines...

Then, I just want to select fron the same file, the first two columns, as a arrays, so I wrote:

double *x, *y, *z;

for ( i=0; i<count; i++ )
{ fscanf (stream,"%le /t %le /t %le", &x[i], &y[i], &z[i]);
}


I tried then to check if the file is read correctly, so I added in the fors's above loop the function :

printf ("\n %le", &x[i]);


At this point, the program crushes, so I suppose something it's not correct...

I would appreciate any suggestions or help in order to be able to "printf" the first 2 columns, so I will know my program reads correctly the data file....

Thank you!

>>fscanf (stream,"%le /t %le /t %le", &x[i], &y[i], &z[i])
Check the return code from this function to make sure it read in what you asked it to. I can guarantee you it isn't working ;)

The return code should be 3, as you are trying the scan 3 numbers.

A tab character is \t, not /t.

Thanks, Hammer!

I corrected the misspelling, but, still, after I include "ptrintf" function (for x, for example), to check what the programs reads, the result is

0.000000e+000

so, I still can't read the input file corrrectly


:(

Something like this, maybe?

Code:

---

#include <stdio.h>
#include <stdlib.h>

int main(void)
{
  const char filename[] = "test.txt";
  FILE *file = fopen(filename, "r");
  if ( file != NULL )
  {
      size_t i, count, size = 10;
      double *x = malloc(size * sizeof(*x));
      double *y = malloc(size * sizeof(*y));
      double *z = malloc(size * sizeof(*z));
      if ( x != NULL && y != NULL && z != NULL )
      {
        /* Read all three columns. */
        for ( count = 0; count < size; ++count )
        {
            if ( fscanf (file ,"%lf%lf%lf", &x[count], &y[count], &z[count]) != 3 )
            {
              break;
            }
        }
        /* Use only the first two columns. */
        for ( i = 0; i < count; ++i )
        {
            printf("x = %f, y = %f\n", x[i], y[i]);
        }
        free(x);
        free(y);
        free(z);
      }
  }
  return 0;
}

---

[edit]
Oops! I had to fix the code to take my own advice! (I previously had %lf in the printf.)
[/edit]

Thank you for your sugestion Dave,


At this time, I have the following:


#include <malloc.h>

#define CALLOC(num, type) ((double*)calloc (num, sizeof(double)))
#define FREE(addr) (free((void*) (addr)))

int i, count;
double *x, *y, *z; // I'll skip the declaration of other
// variables and the other parts
// of the programs (within main func)

int main (void)

{

FILE *stream;
if ( (stream = fopen ( "r42.txt", "r" )) == NULL )
{ printf ("Cannot read the new file\n");
exit (1);
}

count = 373; // returned by another function
// of the program, I have 373 lines
// in each of the 3 columns

x=CALLOC(count, double);
y=CALLOC(count, double);
z=CALLOC(count, double);


for ( i=0; i<count; i++ )
{ fscanf (stream,"%le %le %le", &x[i], &y[i], &z[i]);
printf ("\n %d %le %le %le", i, x[i], y[i], z[i]);
}

FREE(x);
FREE(y);
FREE(z);

fclose (stream);

}



the printf function will give me 373 lines as follows:

0.000000e+000 0.000000e+0 0.000000e+0



so, I don't understand why the input file is not read

Thank you for your help!

What I want here is to read a 3 column input data file, as the folloing:



2.5000000000E+1 1.6285272837E+0 1.2494180202E+0
2.5018749237E+1 1.3162814379E+0 1.9428113699E+0
2.5037498474E+1 1.2828449011E+0 2.7128908634E+0
2.5056249619E+1 1.5575599670E+0 2.9970877171E+0
2.5074998856E+1 1.9759304523E+0 2.5490462780E+0
2.5093750000E+1 2.2521975040E+0 1.6395831108E+0
2.5112499237E+1 2.1530494690E+0 9.4248563051E-1
2.5131248474E+1 1.7716845274E+0 1.0123537779E+0
2.5149999619E+1 1.4909162521E+0 1.7716845274E+0
2.5168748856E+1 1.4909162521E+0 2.7529489994E+0

this data file has 373 line, this number being returned by another function of the frogram, which works fine, so I won't put it here...

What I want is to read this file and to use these numbers in further calculations...


Selecting from my program whe part that is not working, this looks as follows:

-----------------------------------------

#include <malloc.h>

#define CALLOC(num, type) ((double*)calloc (num, sizeof(double)))
#define FREE(addr) (free((void*) (addr)))

int i, count;
double *x, *y, *z; // I'll skip the declaration of other
// variables and the other parts
// of the programs (within main func)

int main (void)

{

FILE *stream;
if ( (stream = fopen ( "r42.txt", "r" )) == NULL )
{ printf ("Cannot read the new file\n");
exit (1);
}

count = 373; // returned by another function
// of the program, I have 373 lines
// in each of the 3 columns

x=CALLOC(count, double);
y=CALLOC(count, double);
z=CALLOC(count, double);


for ( i=0; i<count; i++ )
{ fscanf (stream,"%le %le %le", &x[i], &y[i], &z[i]);
printf ("\n %d %le %le %le", i, x[i], y[i], z[i]);
}

FREE(x);
FREE(y);
FREE(z);

fclose (stream);

}

---------------------------------------------------------



the printf function will give me 373 lines as follows:

0.000000e+000 0.000000e+0 0.000000e+0



so, I don't understand why the input file is not read :(

Thank you for your help!

Thank you all guys for your help...

I got it work.... finally, it turned out to be just a stupid memory problem...
I tworks fine now!

vk :)