1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
|
// Copyright (C) 2018 - IIT Bombay - FOSSEE
// This file must be used under the terms of the CeCILL.
// This source file is licensed as described in the file COPYING, which
// you should have received as part of this distribution. The terms
// are also available at
// http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
// Original Source : https://octave.sourceforge.io/
// Modifieded by: Abinash Singh Under FOSSEE Internship
// Last Modified on : 3 Feb 2024
// Organization: FOSSEE, IIT Bombay
// Email: toolbox@scilab.in
function [Zz, Zp, Zg] = ncauer(Rp, Rs, n)
//Analog prototype for Cauer filter (Cauer filter and elliptic filters are same).
//Calling Sequence
//[Zz, Zp, Zg] = ncauer(Rp, Rs, n)
//Parameters
//n: Filter Order
//Rp: Peak-to-peak passband ripple in dB
//Rs: Stopband attenuation in dB
//Description
//It gives an analog prototype for Cauer filter of nth order, with a Peak-to-peak passband ripple of Rp dB and a stopband attenuation of Rs dB.
//Examples
//n = 5;
//Rp = 5;
//Rs = 5;
//[Zz, Zp, Zg] = ncauer(Rp, Rs, n)
//Zz =
//
// 0.0000 + 2.5546i 0.0000 + 1.6835i -0.0000 - 2.5546i -0.0000 - 1.6835i
//
//Zp =
//
// -0.10199 + 0.64039i -0.03168 + 0.96777i -0.10199 - 0.64039i -0.03168 - 0.96777i -0.14368 + 0.00000i
//
//Zg = 0.0030628
// Dependencies
// ellipap
funcprot(0);
lhs = argn(1)
rhs = argn(2)
if (rhs < 3 | rhs > 3)
error("ncauer : Wrong number of input arguments.")
end
[Zz, Zp, Zg] = ellipap(n, Rp, Rs) ;
// temp fix to permanently fix this change ellipap
Zz = Zz';
Zp = Zp';
endfunction
/*
// Test Case 1 (ncauer 0.1, 60, 7)
[z, p, g] = ncauer(0.1, 60, 7);
assert_checkalmostequal(z, [2.5574 1.5522 1.3295 -2.5574 -1.5522 -1.3295]*%i, 1e-2);
assert_checkalmostequal(p, [-0.3664+0.5837*%i -0.1802+0.9088*%i -0.0499+1.0285*%i -0.3664-0.5837*%i -0.1802-0.9088*%i -0.0499-1.0285*%i -0.4796], 1e-2);
assert_checkalmostequal(g, 7.4425e-03, 1e-2);
// Test Case 2 (ncauer 1.0, 30, 3)
[z, p, g] = ncauer(1.0, 30, 3);
assert_checkalmostequal(z, [1.9536 -1.9536]*%i, 1e-2);
assert_checkalmostequal(p, [-0.2053+0.9870*%i -0.2053-0.9870*%i -0.5597], 1e-2);
assert_checkalmostequal(g, 0.1490, 1e-2);
// Test Case 3 (ncauer 0.25, 50, 6)
[z, p, g] = ncauer(0.25, 50, 6);
assert_checkalmostequal(z, [4.0596 1.6414 1.3142 -4.0596 -1.6414 -1.3142]*%i, 1e-2);
assert_checkalmostequal(p, [-0.4210+0.3665*%i -0.2117+0.8503*%i -0.0550+1.0198*%i -0.4210-0.3665*%i -0.2117-0.8503*%i -0.0550-1.0198*%i], 1e-2);
assert_checkalmostequal(g, 3.1618e-03, 1e-2);
// Test Case 4 (ncauer 0.8, 45, 4)
[z, p, g] = ncauer(0.8, 45, 4);
assert_checkalmostequal(z, [4.1768 1.8543 -4.1768 -1.8543]*%i, 1e-2);
assert_checkalmostequal(p, [-0.3861+0.4640*%i -0.1234+1.0000*%i -0.3861-0.4640*%i -0.1234-1.0000*%i], 1e-2);
assert_checkalmostequal(g, 5.6237e-03, 1e-2);
*/
|
