Thread: Help with Streams

ok this outputs about 100 numbers with the spaces

#include <iostream.h>
#include <fstream.h>
#include <iomanip.h>
#include <stdlib.h>
#include <time.h>
#include <stdio.h>
#include <string.h>




int main()

{
int num[120];
int counter;

int x;

ofstream outstream("digits2.dat");



if(outstream.fail())
{
cout<<"File Problem"<<endl;
exit(1);
}


srand(time(NULL));


for(counter=0; counter<100; counter++)
{
x=1 + rand() % 100;
outstream<<x; // this puts number into file and increments marker/counter to the end of the number

}// this is where it goes back and puts the next number and another space... does this 100 times





outstream.close();

return(0);

}

>>>yea I see some numbers in the file



awesome... see you are halfway there. No reason to get frustrated.


Also...

.put() is used with your ofstream... sorry bout that. I meant it in my head but wrote something different.





Examine this ANSI complient code... how does it differ from your output to file code.

Code:

#include <fstream>
#include <iostream>
#include <stdlib>

using namespace std;

int main ()
{

     // Local variables
     char mychar;        // Character Storage
     int counter=0;        // Integer counter

     char array[5] = "1234";
     
     ofstream outs;     // output buffer
     ifstream ins;      // input buffer

     outs.open("betazep.txt"); // open output file

     if (outs.fail()) // error checking
     {     
          cout << "Output file failure." << endl;
          return 0;
     } // end if


     //********************************//
    

     // Cout array
     cout << array << endl << endl;
      
      
      // Output array to file
      while(counter < 5)
      {

           outs.put(array[counter]);
           outs.put(' ');
           cout << array[counter];
           ++counter;

       }// end while

     outs.close(); // close output file


     // Copying from one file to another**************************
     ins.open("betazep.txt");  // open input file

     if (ins.fail())
     {

         cout << "Input file failure." << endl;
         return EXIT_FAILURE;  // as found in stdlib

     } // end if

     outs.open("venomgts550.txt");  // open output file

     if (outs.fail())  // error checking
    {

          cout << "Output file failure." << endl;
          return 0;

    } // end if

    while (!ins.eof())
    {

         ins.get(mychar);
         if (mychar != ' ')
         {
         outs.put(mychar);
         cout << "copying " << mychar << endl;  // show what is getting copied
         } // end if

     } // end while... file copied without spaces

     ins.close();
     outs.close();

return 0;

} // end main

compile that and see how it works... also try to increase the array size by one and add one more number and then go down and increase the counter < 5 to counter < 6.

Notice that the file manipulation can handle any file size. It is only limited by the end of file.

Its a little confusing to me but it looks like it open betazip.txt then copies it to venomgts550.txt

good... now lets clean it up... try this on your compiler

#include <iostream>
#include <fstream>
#include <stdio>
using namespace std;

int main()

{

int x, counter;

ofstream outstream("digits2.dat");

if(outstream.fail())
{
cout<<"File Problem"<<endl;
return 0;
}

for(counter=0; counter<100; counter++)
{
x=1 + rand() % 100;
outstream << x;
outstream.put(' ');
}

outstream.close();

return(0);

}

>>>Its a little confusing to me but it looks like it open betazip.txt then copies it to venomgts550.txt

It opens betazep.txt and puts 1 2 3 4 into it and closes it.

Then it opens both files and copies betazep.txt over to venomgts550.txt without the spaces.

Like...

1234

Doesn't do much really. But the latter portion could copy an entire text file into another file.

ok i got it to work

I gotta clean my house. Try writing a seperate program that can read the input from the file and view them as integers.

Get it to do just one number and I will show you how to loop through the rest effectively.

Bye for tonight....

Betazep

ok thanx for all your help
good night

Can someone please help me I cant seem to get this input right
this is what i have so far

#include
#include
#include
#include
#include
#include
int main()
{
int array[120];
int x, counter;
ofstream outstream("digits2.dat");
if(outstream.fail())
{
cout<<"File Problem"<return 0;
}
srand(time(NULL));
for(counter=0; counter<100; counter++)
{
x=1 + rand() % 100;
outstream<outstream.put(' ');
}
outstream.close();
ifstream instream("digits2.dat");
instream>>x;
//----------------------------------------------------------------------------------------------------
char mychar;
int integer_counter;
int size_three_char_array[120];
for(int count=0; count<100; count++)
{
instream.get(mychar);
cout<outstream.put(' ');
if ( mychar != ' ')
{
size_three_char_array[integer_counter]; // put the number in an array at position zero for now
integer_counter++; // originally set to 0
}
else {
integer_counter = 0; // if we didn't find a number then we found a space, and we need to clear our counter
}
//----------------------------------------------------------------------------------------------------
}
instream.close();
return(0);
}

bump

where have you gotten with this?

Code:

// Program opens a file filled with integer values seperated by spaces and finds the
// largest value within the file.  Integers must be three digits or less, and the final
// integer must be followed by a space to have it included.  (all which can be modified
// easily within the code)

# include<fstream>
# include<iostream>
# include <stdio>
using namespace std;

int main ()
{

	// Local variables
	ifstream ins;
        char yourfile[100], mynum[4];
        char mychar;
        int count, temp, final = 0;

	cout << "What is the file path/name: ";
	cin  >> yourfile;

	ins.open(yourfile); 

	if (ins.fail())
	{
	   while (ins.fail())
	   {
		cout << "Failure opening input file.  Check file path." << endl << endl
                     << "You entered " << yourfile << endl
                     << "Enter path/name (or X to quit): ";
                cin  >> yourfile;
		
                if ((yourfile[0]=='X')||(yourfile[0]=='x'))
		     return 1;


                ins.open(yourfile);

	   } // end while
	}// end if

        count = 0;

        while (!ins.eof()) // go until file ends
        {
                ins.get(mychar);
                cout << mychar;

                if ((isdigit(mychar))&&(mychar!=' '))
                {
                   mynum[count] = mychar;
                   ++count;
                } // end if

                if (mychar == ' ')
                {
                      count = 0;
                      temp = atoi(mynum);

                      if (temp > final)
                      {
                         final = temp;
                      }

                      mynum[0] = '\0';
                      mynum[1] = '\0';
                      mynum[2] = '\0';
                } // end if

                 
         }// end while


    	ins.close();

        cout << endl << endl <<"The largest number in the file was "
             << final;



return 0;
}

That does it pretty much. I cannot help you anymore. you put the two together and try to figure it out. There are other ways as well....