Basics of MATLAB and Beyond

Now we need to get the handles of all the lines. We could have said h =plot(y) to get them, but for now we use the get function:h = get(gca,’children’)The gca function returns the handle of the current axes, andget(gca,’children’) returns the handles of all the current axes’ children(the lines on the plot). Now we want to change the thicknesses ofthe lines. We set up a vector of line widths with as many elements asthere are lines:widths = linspace(.1,10,length(h));The widths of the lines will vary from a minimum of 0.1 to a maximumof 10. We use a for-loop to change the width of each of the lines:for i = 1:10set(h(i),’linewidth’,widths(i));end24 DemosThe matlab demos are well worth browsing. You can learn about asubject (often reading references are given), as well as learning aboutmatlab’s capabilities. Of interest to sonar and radar signal processors ismatlab’s Higher Order Spectral Analysis toolbox containing, for example,functions for direction of arrival estimation (beamforming plus othermethods), time-frequency distributions, and harmonic estimation. Typehelp hosa for a list of functions in the Higher Order Spectral Analysistoolbox. Browsing the demos or doing a keyword search may save youfrom writing your own matlab code and re-inventing the wheel. Typedemo to get the panel:c○ 2000 by CRC Press LLC