Generalized rectangular time-frequency distribution.
[TFR,T,F]=tfrgrd(X) [TFR,T,F]=tfrgrd(X,T) [TFR,T,F]=tfrgrd(X,T,N) [TFR,T,F]=tfrgrd(X,T,N,G) [TFR,T,F]=tfrgrd(X,T,N,G,H) [TFR,T,F]=tfrgrd(X,T,N,G,H,RS) [TFR,T,F]=tfrgrd(X,T,N,G,H,RS,MOVERN) [TFR,T,F]=tfrgrd(X,T,N,G,H,RS,MOVERN,TRACE) [TFR,T,F]=tfrgrd(...,'plot')
A Nx elements vector (auto-GRD) or a Nx by 2 array signal (cross-GRD).
a real Nt vector : time instant(s) (default: 1:NX).
a positive integer: the number of frequency bins (default:NX).
a real vector with odd length: the time smoothing window, (default :Hamming(N/10)).
It will be normalized such as the middle point equals 1 to preserve signal energy.
real vector with odd length: the frequency smoothing window,(default: Hamming(N/4)).
It will be normalized such as the middle point equals 1 to preserve signal energy.
a positive scalar: the kernel width (default : 1).
a positive scalar: the dissymmetry ratio (default : 1).
if nonzero,the progression of the algorithm is shown (default : 0).
if one input parameter is 'plot', tfrqview is called and the time-frequency representation will be plotted.
A real N by Nt array: the time-frequency representation.
A N vector of normalized frequencies.
signal if auto-GRD, or [X1,X2] if cross-GRD.
time instant(s) (default : 1:length(X)).
number of frequency bins (default : length(X)).
time smoothing window, G(0) being forced to 1. (default : Hamming(N/10)).
frequency smoothing window, H(0) being forced to 1. (default : Hamming(N/4)).
kernel width (default : 1).
dissymmetry ratio (default : 1).
if nonzero, the progression of the algorithm is shown (default : 0).
if one input parameter is 'plot', tfrgrd runs tfrqview. and TFR will be plotted
time-frequency representation.
vector of normalized frequencies.
tfrgrd computes the Generalized Rectangular distribution of a discrete-time signal X, or the cross GRD representation between two signals.
Interactive use
N=128 sig=fmlin(N,0.05,0.3)+fmlin(N,0.15,0.4); g=window("kr",9,3*%pi); h=window("kr",27,3*%pi); t=1:N; tfrgrd(sig,t,N,g,h,36,1/5,1,'plot'); | ![]() | ![]() |
Non interactive use
N=128; sig=fmlin(N,0.05,0.3)+fmlin(N,0.15,0.4); g=window("kr",9,3*%pi); h=window("kr",27,3*%pi); t=1:N; [TFR,T,F]=tfrgrd(sig,t,N,g,h,36,1/5); clf;gcf().color_map= jetcolormap(128); grayplot(T,F,TFR'); | ![]() | ![]() |