#include "MusimatTutorial.h"Go to the source code of this file.
Functions | |
| MusimatTutorialSection (B0201b) | |
| RealList | pythagoreanChromatic (1.0/1.0, 256.0/243.0, 9.0/8.0, 32.0/27.0, 81.0/64.0, 4.0/3.0, 1024.0/729.0, 3.0/2.0, 128.0/81.0, 27.0/16.0, 16.0/9.0, 243.0/128.0) |
| Static Void | para1 () |
| Real | pitchToHz (Pitch p, Real refC, RealList scale) |
| Static Void | para2 () |
| MusimatTutorialSection | ( | B0201b | ) |
Definition at line 2 of file B0201b.cpp.
References para1(), and para2().
00002 { 00003 Print("*** Pythagorean Chromatic Scale ***"); 00004 /***************************************************************************** 00005 00006 Pythagorean Chromatic Scale 00007 00008 We can compute the frequency of a Pitch in Pythagorean 00009 chromatic tuning, assuming a reference such as A4 equals 440 Hz. We start by computing the fre- 00010 quency of Pythagorean middle C from the reference frequency, using equation (3.11). 00011 *****************************************************************************/ 00012 para1(); // Step into this function to continue the tutorial 00013 para2(); // Step into this function to continue the tutorial 00014 }
| Static Void para1 | ( | ) |
Definition at line 28 of file B0201b.cpp.
References para2().
00028 { 00029 /***************************************************************************** 00030 Last, we define a variation of the pitchToHz() function. This version has the same name but 00031 takes three arguments instead of one. When supplied with a certain Pitch p, it returns the fre- 00032 quency corresponding to its Pythagorean intonation as a Real value in hertz. 00033 *****************************************************************************/ 00034 para2(); 00035 }
| Static Void para2 | ( | ) |
Definition at line 47 of file B0201b.cpp.
References pitchToHz(), pythagoreanChromatic(), and R.
00047 { 00048 /***************************************************************************** 00049 The Return() statement calculates the frequency of the key from the reference frequency 00050 times the ratio for that degree, then adjusts it for the proper octave. 00051 00052 We define the reference frequencies in Musimat as follows: 00053 *****************************************************************************/ 00054 00055 Real R = 440.0; 00056 Real cPi4 = R * 16.0/27.0; // Pythagorean middle C, 260.74 Hz 00057 00058 /***************************************************************************** 00059 Finally, we call pitchToHz() with the pitch we want, the Pythagorean reference 00060 frequency, and the ratios of the Pythagorean scale: 00061 *****************************************************************************/ 00062 00063 Print("Pythagorian A4=", pitchToHz(A4 , cPi4, pythagoreanChromatic)); 00064 00065 /***************************************************************************** 00066 This prints A4=440.0, and 00067 *****************************************************************************/ 00068 00069 Print("Pythagorian C4=", pitchToHz(C4 , cPi4, pythagoreanChromatic)); 00070 00071 /***************************************************************************** 00072 prints C4=260.74, as expected. 00073 00074 *****************************************************************************/ 00075 }}
| Real pitchToHz | ( | Pitch | p, | |
| Real | refC, | |||
| RealList | scale | |||
| ) |
Definition at line 37 of file B0201b.cpp.
References key().
00041 { 00042 Integer key = PitchClass(p) + Accidental(p); // get key from pitch 00043 Real oct = Octave(p); // get octave from pitch 00044 Return(refC * scale[key] * Pow(2.0, (oct - 4)));// compute frequency 00045 }
| RealList pythagoreanChromatic | ( | 1.0/1. | 0, | |
| 256.0/243. | 0, | |||
| 9.0/8. | 0, | |||
| 32.0/27. | 0, | |||
| 81.0/64. | 0, | |||
| 4.0/3. | 0, | |||
| 1024.0/729. | 0, | |||
| 3.0/2. | 0, | |||
| 128.0/81. | 0, | |||
| 27.0/16. | 0, | |||
| 16.0/9. | 0, | |||
| 243.0/128. | 0 | |||
| ) |
Referenced by para2().
1.4.7