Merge pull request #17 from avinashlalotra/masterHEADmaster

Abinash's Work

1 files changed, 37 insertions, 28 deletions

diff --git a/macros/shanwavf.sci b/macros/shanwavf.sci
index a597214..e088f60 100644
--- a/macros/shanwavf.sci
+++ b/macros/shanwavf.sci
@@ -1,30 +1,39 @@
+/*Description
+    Compute the Complex Shannon wavelet.
+    The complex Shannon wavelet is defined by a bandwidth parameter fb, a wavelet center frequency fc, and the expression
+    psi(x) = f * b^{1/2}sinc(fb . x) e^{2 pi i f c x}
+    on an n-point regular grid in the interval of lb to ub.
+Calling Sequence
+    [psi, x]= shanwavf(lb, ub, n, fb, fc)
+Input  Parameters
+    lb, ub (Real valued scalers) : Interval endpoints lb ≤ ub, specified as a pair of real-valued scalars.
+    n (Real valued integer strictly positive)` : Number of regularly spaced points in the interval [lb,ub], specified as a positive integer.
+    fb	: Time-decay parameter of the wavelet (bandwidth in the frequency domain). Must be a positive scalar.
+    fc	: Center frequency of the complex Shannon wavelet, specified as a positive scalar.
+Output Parameters
+     psi : Complex Shannon wavelet evaluated on the n point regular grid x in the interval [lb,ub], returned as a 1-by-n vector.
+     x   : Grid where the complex Shannon wavelet is evaluated, returned as a 1-by-n vector. The sample points are evenly distributed between lb and ub.
+Examples
+      1.[a,b]=shanwavf (2,8,3,1,6)
+           a =   [-3.8982e-17 + 1.1457e-31i   3.8982e-17 - 8.4040e-31i  -3.8982e-17 + 4.5829e-31i]
+           b =   [2   5   8]   */
 function [psi,x]=shanwavf(lb,ub,n,fb,fc)
-
-// Complex Shannon Wavelet
-// Calling Sequence
-//	[psi,x]=shanwavf(lb,ub,n,fb,fc)
-// Parameters
-//	lb: Real or complex valued vector or matrix
-//	ub: Real or complex valued vector or matrix
-//	n: Real valued integer strictly positive
-//	fb: Real or complex valued vector or matrix, strictly positive value for scalar input
-//	fc: Real or complex valued vector or matrix, strictly positive value for scalar input
-// Description
-//	This is an Octave function
-//	This function implements the complex Shannon wavelet function and returns the value obtained. The complex Shannon wavelet is defined by a bandwidth parameter FB, a wavelet center frequency FC on an N point regular grid in the interval [LB,UB].
-// Examples
-// 1.	[a,b]=shanwavf (2,8,3,1,6)
-//	a =   [-3.8982e-17 + 1.1457e-31i   3.8982e-17 - 8.4040e-31i  -3.8982e-17 + 4.5829e-31i]
-//	b =   [2   5   8]
-// 2.	[a,b]=shanwavf(1,2,1,[2,2;i,2],[-1,2;-i,i])
-//	a =   [-5.5128e-17 - 2.7005e-32i  -5.5128e-17 + 5.4010e-32i;
-//	       8.6404e+06 + 8.6404e+06i  -1.9225e-22 - 0.0000e+00i]
-//	b =  2
-
-funcprot(0);
-rhs=argn(2);
-if (rhs~=5) then
-	error ("Wrong number of input arguments.")
-else [psi,x]=callOctave("shanwavf",lb,ub,n,fb,fc)
-end
+    funcprot(0);
+    rhs=argn(2);
+    if (rhs~=5) then
+        error ("Wrong number of input arguments.")
+    else 
+        if (n <= 0 || floor(n) ~= n)
+            error("n must be an integer strictly positive");
+        elseif (fc <= 0 || fb <= 0)
+            error("fc and fb must be strictly positive");
+        end
+        x = linspace(lb,ub,n);
+        sincx=x;
+        for i=1:n
+            sincx(i)=sin(fb*x(i)*%pi)/(fb*x(i)*%pi);
+        end    
+        psi = (fb.^0.5).*(sincx.*exp(2.*%i.*%pi.*fc.*x));
+    end
 endfunction
+