function dummy(TF,thresh)
% LOGarithmic scaled TF plot,
% converts matrix to the file deleteme.eps
% draws a box around it and puts on tick marks
% labels axes as time and frequency
%
% mat2eps_tf(A,thresh)            % takes abs value, inverts, LOG scales 0..255
% or mat2eps_logtf(tf(_____,M,N),thresh)
%
% thresh defaults to 1/300 maximum value (-60 dB if its a power spectrum)
%                                        (-30 dB if its a magnitude spectrum)
%
% returns nothing

TFabs = abs(TF);  % in case it is complex
if nargin == 1  % no thershold provided
  thresh = max2(TF)/300;  % -30db -60db volts seems like a good value to default
end%if

logTF = log(clip(TFabs,thresh));
clear TFabs

big = 1000; % 10000dBw or 20000dBv, log values usually like only -8 or -10
img = 255 - scaler2(logTF+big); % negative to save toner
                                 % + big since logs may be negative
clear logTF
img = flipud(img).';    % flipud is for postscript being upside down
                        % transpose is because .mat is not TV order
save deleteme img
clear img
!mat2eps_tf deleteme.mat deleteme.eps
delete deleteme.mat