1 files changed, 62 insertions, 49 deletions
diff --git a/macros/cheb1ap.sci b/macros/cheb1ap.sci
index 361f272..51bc03b 100644
--- a/macros/cheb1ap.sci
+++ b/macros/cheb1ap.sci
@@ -1,51 +1,64 @@
-function [z, p, g] = cheb1ap (n, Rp)
-//This function designs a lowpass analog Chebyshev type I filter.
-//Calling Sequence
-//[z, p, g] = cheb1ap (n, Rp)
-//[z, p] = cheb1ap (n, Rp)
-//p = cheb1ap (n, Rp)
-//Parameters 
-//n: Filter Order
-//Rp: Peak-to-peak passband ripple
-//z: Zeros
-//p: Poles
-//g: Gain
-//Description
-//This is an Octave function.
-//It designs a lowpass analog Chebyshev type I filter of nth order and with a Peak-to-peak passband ripple of Rp.
-//Examples
-//[z, p, g] = cheb1ap (10, 20)
-//z = [](0x0)
-//p =
-//
-// Columns 1 through 6:
-//
-//  -0.00157 - 0.98774i  -0.00456 - 0.89105i  -0.00709 - 0.70714i  -0.00894 - 0.45401i  -0.00991 - 0.15644i  -0.00991 + 0.15644i
-//
-// Columns 7 through 10:
+// Copyright (C) 2018 - IIT Bombay - FOSSEE
 //
-//  -0.00894 + 0.45401i  -0.00709 + 0.70714i  -0.00456 + 0.89105i  -0.00157 + 0.98774i
-//
-//g =  1.9630e-04 - 6.3527e-22i
-
-funcprot(0);
-lhs = argn(1)
-rhs = argn(2)
-if (rhs < 2 | rhs > 2)
-error("Wrong number of input arguments.")
-end
-
-select(rhs)
-	
-	case 2 then
-		if(lhs==1)
-		z = callOctave("cheb1ap", n, Rp)
-		elseif(lhs==2)
-		[z, p] = callOctave("cheb1ap", n, Rp)
-		elseif(lhs==3)
-		[z, p, g] = callOctave("cheb1ap", n, Rp)
-		else
-		error("Wrong number of output argments.")
-		end
-	end
+// 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
+// Author:Sonu Sharma, RGIT Mumbai
+// Organization: FOSSEE, IIT Bombay
+// Email: toolbox@scilab.in
+
+function [z, p, g] = cheb1ap (n, Rp)
+    //This function designs a lowpass analog Chebyshev type I filter.
+
+    //Calling Sequence
+    //[z, p, g] = cheb1ap (n, Rp)
+
+    //Parameters
+    //n: Filter Order
+    //Rp: Peak-to-peak passband ripple (in dB)
+    //z: Zeros
+    //p: Poles
+    //g: Gain
+
+    //Description
+    //It gives a lowpass analog Chebyshev type I filter of nth order and with a Peak-to-peak passband ripple of Rp.
+
+    //Examples
+    //[z, p, g] = cheb1ap (10, 3)
+    //Output :
+    // g  =
+    //
+    //    0.0019578
+    // p  =
+    //
+    //  - 0.0138320 - 0.9915418i
+    //  - 0.0401419 - 0.8944827i
+    //  - 0.0625225 - 0.7098655i
+    //  - 0.0787829 - 0.4557617i
+    //  - 0.0873316 - 0.1570448i
+    //  - 0.0873316 + 0.1570448i
+    //  - 0.0787829 + 0.4557617i
+    //  - 0.0625225 + 0.7098655i
+    //  - 0.0401419 + 0.8944827i
+    //  - 0.0138320 + 0.9915418i
+    // z  =
+    //
+    //     []
+
+    funcprot(0);
+    lhs = argn(1)
+    rhs = argn(2)
+    if (rhs < 2 | rhs > 2)
+        error("cheb1ap: Wrong number of input arguments.")
+    end
+
+    Rpf = 10 ^ (-Rp/20);    //passband pick to pick ripple in fraction
+    rp = 1 - Rpf ;          //analpf function compitable passband ripple (delta-p)
+    [hs,p,z,g]=analpf(n,"cheb1",[rp 0],1); //cutoff frequency of 1 rad/sec for prototype filter
+    p = p' ;
+    z = z' ;
+    g = abs(g);
+
 endfunction