Category: Numerical Analysis

// FrequencyKey.cpp : Defines the entry point for the console application.
// James Pate Willims, Jr. (c) All Applicable Rights Reserved

#include "stdafx.h"
#include <math.h>
#include <iomanip>
#include <iostream>
#include <string>
#include <vector>
using namespace std;

vector<string> pnote;
double a = pow(2.0, 1.0 / 12.0);
double f0 = 440.0, gStrF[6];
double e2, a2, d3, g3, b3, e4;
double pfreq[9 * 12];
int offset = 0;

double fn(int n)
{
	return f0 * pow(a, n);
}

void printFrequency(char note, int octave, double frequency)
{
	cout << note << "\t" << octave << "\t";
	cout << setw(6) << fixed << setprecision(2);
	cout << frequency << endl;
}

int main()
{
	for (int octave = 0; octave <= 8; octave++)
	{
		pnote.push_back("C");
		pnote.push_back("C#");
		pnote.push_back("D");
		pnote.push_back("D#");
		pnote.push_back("E");
		pnote.push_back("F");
		pnote.push_back("F#");
		pnote.push_back("G");
		pnote.push_back("G#");
		pnote.push_back("A");
		pnote.push_back("A#");
		pnote.push_back("B");
	}

	pfreq[0] = 16.35;
	pfreq[1] = 17.32;
	pfreq[2] = 18.35;
	pfreq[3] = 19.45;
	pfreq[4] = 20.6;
	pfreq[5] = 21.83;
	pfreq[6] = 23.12;
	pfreq[7] = 24.5;
	pfreq[8] = 25.96;
	pfreq[9] = 27.5;
	pfreq[10] = 29.14;
	pfreq[11] = 30.87;
	
	for (int octave = 1; octave <= 8; octave++)
	{
		for (int i = 0; i < 12; i++)
		{
			pfreq[octave * 12 + i] = 2.0 * pfreq[(octave - 1) * 12 + i];
		}
	}

	gStrF[0] = e2 = fn(offset - 29);
	gStrF[1] = a2 = fn(offset - 24);
	gStrF[2] = d3 = fn(offset - 19);
	gStrF[3] = g3 = fn(offset - 14);
	gStrF[4] = b3 = fn(offset - 10);
	gStrF[5] = e4 = fn(offset - 5);

	cout << "Guitar\tOctave\tFrequency (Hz)" << endl;
	
	printFrequency('E', 2, e2);
	printFrequency('A', 2, a2);
	printFrequency('D', 3, d3);
	printFrequency('G', 3, g3);
	printFrequency('B', 3, b3);
	printFrequency('E', 4, e4);
	
	cout << endl;
	cout << "Piano Keys" << endl << endl;

	for (int octave = 0; octave <= 8; octave++)
	{
		for (int i = 0; i < 2; i++)
		{
			cout << octave << '\t';

			for (int j = 0; j < 6; j++)
			{
				{
					cout << pnote[(12 * octave + 6 * i + j) % 12] << '\t';
					cout << pfreq[(12 * octave + 6 * i + j)] << '\t';
				}
			}

			cout << endl;
		}
	}

	return 0;
}