Reading from text file

[jingojam]

I have edited the program and it seems the first Frequency value from my text file is being read and not the rest. How can I create a loop that will keep reading from the text file and display different values for Frequency and Velocity and not same values? For Time, since it is an increment of 100 a loop worked without calling the time from the text file which is not correct as it should read from the text file in a loop. Also, Frequency values are long decimal points not displayed as seen with 9 decimal point since am using double data type. my text file loops like this:
0

100

200

300

400

500

600

5.500000040

5.500000095

5.500000230

5.500001800

5.500000870

5.500000065

5.500000370

Problem:
For a radar transmitting at frequency f (t), the difference in transmitted and received frequencies due to a target moving at speed v (m/s) relative to the radar that is, directly toward or away from the radar is given by

(f (r)- f (t)) / f (t) = 2v/c

where f (r) is the received frequency and c is the speed of light (3x10^8m/s). A weather service station at a major municipal airport is using a C-band Doppler radar f (t) = 5.5GHz). During a severe thunderstorm, the following received frequencies are observed:

Time(s) Frequency (GHz)
0 5.500000040
100 5.500000095
200 5.500000230
300 5.500001800
400 5.500000870
500 5.500000065
600 5.500000370

Write a program that scans these data and displays a table showing the data along with a third column displaying the Doppler velocities of the winds relative to the radar.

  #include "stdafx.h"
#include <iostream>
#include <iomanip>
#include <fstream>
#include <cmath>
using namespace std;

int _tmain(int argc, _TCHAR* argv[])
{
	int n;
	int Time = 0;
	double Frequency;
	double Velocity = 0;//size of array more than number of entries in data file

	ifstream infile("C:\\My documents\\frequency.txt", ios::in);//open the text file
	infile >> Time;
	infile >> Frequency;
	while (!infile.eof())
	{

		infile >> Frequency;
		Velocity = (((Frequency - 5.5) / 5.5) * 3e+8) / 2;
		Frequency++;
	}
	cout << setw(1) << "Time" << setw(15) << "Frequency" << setw(20) << "Velocity" << endl;
	for (Time = 0; Time < 700; Time)//counter loop of the first values from 0 to 600 increment
	{
		cout << setw(1) << Time << setw(15) << Frequency << setw(20) << Velocity << endl;
		Time += 100;//Print out for the table with values.
	}

	infile.close();//input file is closed.
	system("PAUSE");//will wait for the user to end the console
	return 0;//End of the main program
}

[keskiverto]

Is your input file really like:

time1
time2
..
timeN
freq1
freq2
..
freqN

If so, you would have to know N before reading the file.

Things are much simpler, if the file actually has:

time1
freq1
time2
freq2
..
timeN
freqN

[jingojam]

I changed the file like above and now not printing anything.

0
5.500000040
100                        
5.500000095
200                           
5.500000230
300                           
5.500001800
400                           
5.500000870
500                           
5.500000065
600 
5.500000370
  

[Chervil]

I thought the input file looked like this:

0 5.500000040
100 5.500000095
200 5.500000230
300 5.500001800
400 5.500000870
500 5.500000065
600 5.500000370

and hence the program needs to repeatedly read the two values, time and frequency.

As a suggestion, it's not a good idea to change the input file, it's just adding more uncertainty. Try to keep things nailed down firmly and the target will be easier to hit.