Column count from data file

This is a discussion on Column count from data file within the C Programming forums, part of the General Programming Boards category; Hi all, I have a dat file called customer.dat with this content: 0 1.1 2 -0.3 4 ... 5 6 ...

  1. #1
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    Column count from data file

    Hi all,

    I have a dat file called customer.dat with this content:

    0 1.1 2 -0.3 4 ...
    5 6 7 8 9 ...
    10.1 11 12 13 99 ...
    ...
    ...

    I have no prior idea about number of rows and columns. Below a sample code I have written using fgets. the output gives the number of rows. but I also want to calculate number of columns.

    can anybody give me any idea...




    Code:
    #include <stdio.h>
    #include <string.h>
    #include <stdlib.h>
    
    int main() {
      FILE *dataFile;
      char fileName[100];
      char customer[100];
      int nRow = 0;
    
    
      printf("Enter the name of the file: ");
      fgets(fileName, sizeof(fileName), stdin);
    
      if((dataFile = fopen(fileName, "r")) == NULL) {
    	 printf("Error Opening File.\n");
    	 exit(1);
    	 }
      
      while( fgets(customer, sizeof(customer), dataFile) != NULL ) {
    	 nRow++;
    	 printf("Row %d: %s\n",nRow, customer);
    	 }
    
      fclose(dataFile);
      return 0;
      }

  2. #2
    uint64_t...think positive xuftugulus's Avatar
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    Looks good to me. Dev-cpp is your IDE? I see the weirdly aligned closing brace...
    Code:
    ...
        goto johny_walker_red_label;
    johny_walker_blue_label: exit(-149$);
    johny_walker_red_label : exit( -22$);
    A typical example of ...cheap programming practices.

  3. #3
    Registered User hk_mp5kpdw's Avatar
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    Once you've got a line of data, you can then try to sscanf the line in a loop picking out one number each iteration of the loop and incrementing a counter.
    "Owners of dogs will have noticed that, if you provide them with food and water and shelter and affection, they will think you are god. Whereas owners of cats are compelled to realize that, if you provide them with food and water and shelter and affection, they draw the conclusion that they are gods."
    -Christopher Hitchens

  4. #4
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    Thanks hk_mp5kpdw. I got my answer. here is the final code. Please tell me if there is any scope of improvements.

    Code:
    #include <stdio.h>
    #include <string.h>
    #include <stdlib.h>
    
    int main() {
      FILE *dataFile;
      char fileName[100];
      char customer[100];
      int nRow = 0, nCol = 0, n=0;
      char *line;
      char entry[11];
    
      printf("Enter the name of a ascii file: ");
      fgets(fileName, sizeof(fileName), stdin);
    
    
    
      if((dataFile = fopen(fileName, "r")) == NULL) {
    	 printf("Error Opening File.\n");
    	 exit(1);
    	 }
    
      while((line = fgets(customer, sizeof(customer), dataFile)) != NULL ) {
    	 while(sscanf(line, "%10s%n", entry, &n ) == 1 ) {
    		nCol++;
    	        line += n;
    		 }
    
    	 nRow++;
    	 printf("Column Entries: %d Row %d: %s\n",nCol, nRow, customer);
    	 nCol = 0;
    	 }
    
      fclose(dataFile);
      return 0;
     
    }
    BTW I am using Borland IDE.

  5. #5
    CSharpener vart's Avatar
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    it is enough to parse one line to determine number of columns

    dataFile = fopen(fileName, "r")
    you need to remove '\n' first from the filename
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  6. #6
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    Thanks for your comment. I need to check missed entry in the data file. so i keep counting the columns in each row. Why I need to remove '\n' first from the filename?

  7. #7
    CSharpener vart's Avatar
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    Quote Originally Posted by spiit231 View Post
    Why I need to remove '\n' first from the filename?
    Otherwise fopen will fail
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

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