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How to read a Value from Text File and store it in Variables

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Old   October 26, 2020, 02:45
Default How to read a Value from Text File and store it in Variables
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Amirreza Niazmehr
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Hi guys
This is my text file (Data.txt):

rho_0 10
kp_0 8
Beta_kp 6
x_min 5
x_max 8
y_min 9
y_max 5
z_min 4
z_max 7

I want to read from this text file line by line and store each Value in the parameter at the same line. for example, for the first line store 10 in rho_0. I have written as below.At the next end I want to use x_min and x_max ... to calculate Volume. I mean
Volume=(x_max-x_min)*(y_max-y_min)*(z_max-z_min).
I have written this code (as below) in C and now I want to use it in my UDF.
First I want to define the Macros and then use this code.
I just want to know if my code works, if I first use and define the proper Macros. I mean,is the body of my code proper for using in UDF?

Code:
#include <stdio.h>
#include <math.h>
#include <stdlib.h>


int main()
{
    double rho_0, kp_0, Beta_kp;
    double x_min, x_max ,y_min ,y_max ,z_min, z_max, V_plasmazone;
	char param_name[100];

    FILE *inputfile;



    /*char inputpath[100];
    char path [100] ;
    strcpy(inputpath, path);
    strcat(inputpath, "Data.txt");
    inputfile = fopen(inputpath, "r");


    if(inputfile)
    {
        ScanCheck(fscanf(inputfile, "%s", inputpath), 1, inputfile, "Data.txt", 1);
        strcat(path, inputpath);
        strcat(path, "/");
    }
    else
    {
        Error("Error opening input.txt - file!");
    }*/


  inputfile =fopen ("Data.txt","r") ;
    if(inputfile == NULL) {
               perror("Unable to open file!");
               exit (1);
            }





   fscanf(inputfile, "%s %lf\n", param_name, &rho_0);
   printf("%s %lf\n", param_name, rho_0);
   fscanf(inputfile, "%s %lf\n", param_name, &kp_0);
   printf("%s %lf\n", param_name, kp_0);
   fscanf(inputfile, "%s %lf\n", param_name, &Beta_kp);
   printf("%s %lf\n", param_name, Beta_kp);
   fscanf(inputfile, "%s %lf\n", param_name, &x_min);
   printf("%s %f\n", param_name, x_min);
   fscanf(inputfile, "%s %lf\n", param_name, &x_max);
   printf("%s %f\n", param_name, x_max) ;
   fscanf(inputfile, "%s %lf\n", param_name, &y_min);
   printf("%s %f\n", param_name, y_min);
   fscanf(inputfile, "%s %lf\n", param_name, &y_max);
   printf("%s %f\n", param_name, y_max);
   fscanf(inputfile, "%s %lf\n", param_name, &z_min);
   printf("%s %f\n", param_name, z_min);
   fscanf(inputfile, "%s %lf\n", param_name, &z_max);
   printf("%s %f\n", param_name, z_max);


 V_plasmazone = ( x_max - x_min )*( y_max - y_min )*( z_max - z_min );
 printf( "V_plasmazone %lf\n", V_plasmazone );



              fclose(inputfile);
              return 0;
}
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Old   October 26, 2020, 08:40
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pakk will become famous soon enough
To use it in Fluent, you should not make it main(), but use a Fluent Macro. Probably EXECUTE_ON_DEMAND is appropriate here; you can then tell Fluent to execute this code whenever you want (look in help to find out how if you don't know yet).
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Old   October 29, 2020, 07:00
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Alexander
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AlexanderZ will become famous soon enoughAlexanderZ will become famous soon enough
I agree with Pakk, you do propably want to use execute on demand macro
read Ansys Fluent Customization manual for good examples
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Old   October 29, 2020, 09:24
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Amirreza Niazmehr
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Thanks alot guys for your help
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Old   February 16, 2024, 17:20
Default problem with read file
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amina
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hi everyone ,

I want to know if my data file (containing 20,000 values) is being read by the udf. To do this, I've created a small program that reads the data from the data.txt file and prints it to another file (data1.txt).
My program compiles well, the library is created and I've hooked my udf to execute on demand.
The data.txt file contains 4 values:
0.2
0.2
0.1
0.1
results on file data1.txt are :
0.000 0.000 0.000 0.000

????????? where is the problem????

this is my udf:

#include "udf.h"
double coef[4];


DEFINE_ON_DEMAND(lire)
{

FILE* rfile;
FILE* rfile1;

rfile = fopen("C:\\Codes\\data.txt", "r");
rfile1 = fopen("C:\\Codes\\data1.txt", "w");
int i;
i = 0;
for (i = 0; i <4; i++)
{
fscanf(rfile, "%f", &coef[i]);
fprintf(rfile1, "%f", coef[i]);
}
fclose(rfile);
fclose(rfile1);
}
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Old   April 5, 2024, 15:14
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Hey, I have the exact same problem. I get zeros when I compile and view the output. Did you resolve this?

Any help is appreciated,
Thanks
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