Thread: I/O streams

The following below is a function in my program. I am supposed to find out the frequency of the letters of the alphabet in the input file. The problem is that i can't get any frequency value after the letter a. I was wondering how to read the text each time a new letter is asked for and can i set my counter back to 0 every time.
Thanks

here is the function definition:

Code:

void read_data(ifstream& input)
{
	char alpha[26] ;
	alpha[0]= 'a';
	alpha[1]= 'b';
	alpha[2]= 'c';
	alpha[3]= 'd';
	alpha[4]= 'e';
	alpha[5]= 'f';
	alpha[6]= 'g';
	alpha[7]= 'h';
	alpha[8]= 'i';
	alpha[9]= 'j';
	alpha[10]= 'k';
	alpha[11]= 'l';
	alpha[12]= 'm';
	alpha[13]= 'n';
	alpha[14]= 'o';
	alpha[15]= 'p';
	alpha[16]= 'q';
	alpha[17]= 'r';
	alpha[18]= 's';
	alpha[19]= 't';
	alpha[20]= 'u';
	alpha[21]= 'v';
	alpha[22]= 'w';
	alpha[23]= 'x';
	alpha[24]= 'y';
	alpha[25]= 'z';
	cout<<"The Letter Frequencies are:"<<endl;
	char ch;
	double sum =0;
	double frequency;
	int counter = 0; 
	for (int i =0; i<26;i++)
	{
			int counter = 0;
			while (input.get(ch))
			{
				if (!islower(ch))
				{
					tolower(ch);
				}
				if (ch == alpha[i])
				{
					counter ++;
				}
				if (i<1)
				{
					if(isalpha(ch))
					{
					sum ++;
					}
				}
				
			}
			frequency = (counter/sum)*100;
	cout<<alpha[i]<<" = "<<frequency<<" %"<<"\n";
		
			
	}		
}

so can anyboady help me with my problem?
(trying to get the text to be read for each letter of the alphabet)

I personally would use a loop to initialize this 26 element array instead of writing each line out!!!

i would too but i have time and i don't want the user to enter the values they are predetermined (unless of course there is a way for the compiler to use the alphabet)

thanks you gave me a good idea. Now i'll have to see if it will work after i type it up.

It's very hard to write a program without any mistakes from the first time( ot at least for me ), it's very notmal to have some errors while writting the program, I don't think you should be very concerned with it.

They say one should spend 90% working on the code in paper and 10% hands on; of course, I spend 90% on the computer and the other 10% scratching my head trying to figure out what's wrong.

You can write punct, chars, digits etc using a simple for loop so that you can test your algo, or put it in a function and write the stuff many times

Code:

for(int i = 0; i < 127; i++)
{
   if(isalpha(i) || isdigit(i) || ispunct(i))
      outFile << (char)i;
}

As for your function, I'm not positive as to what you need. The number of times each of the 26 alpha chars shows up (yikes) versus how many lower case letters there are among the total count of characters. The latter shouldn't be too difficult. I'm not saying that this is the best method but it *should* work in counting the type of each character.

Code:

void readFile(ifstream& input)
{
  char dataIn;
  float digits, total, lcase, ucase;
	
  lcase = ucase = digits = total = 0;
	
  input >> dataIn;
	
  while(input)
  {
     if(islower(dataIn))
        lcase++;
		
    else if(isupper(dataIn))
       ucase++;
		
    else if(isdigit(dataIn))
      digits++;
		
    total++;
    input >> dataIn;
  }

  cout << "The freq of lowr case is " lcase/total; // etc
}

the problem that i am trying to solve is to find out the total number of each letter of the alphabet that appears in a text, find the amount of times each one appears in teh whole text and then get the frequency by dividing the amount of times one leeter appears by the total amount of letters present and multipying it by 100.

thank you for those who helped me. The program is up and running. BTW, the code for program is intended to help decifering encrypted messages.

oh one more thing, does anyone know how to increase the amount of lines that the output can show on the screen because i can only see around 20 lines or so. I need the whole output.