auto correlation plotting using function

i dont understand a section of the function code which makes the auto correlation plotted by holding space bar which plots the next value of the correlation as long as i move the time shiftted signal under the correlated signal with space bar.

that section of the code starts at line 48

normalised_shift_size = 2*plot_width/(num_steps-1);

corr_seg_len = length(rxy)/num_steps;

for k = 1 : num_steps

if(k > 1)

new_pos = get(mid_ax_h,'position') + [normalised_shift_size 0 0 0];

set(mid_ax_h,'position', new_pos);

end

set(corr_h, 'Ydata', [rxy(1:round(corr_seg_len*k)) ones(1,length(rxy)-round(corr_seg_len*k))*NaN])

pause

end

Answer 1

[Image Analyst]

That's what the pause function does. If you want more info, look up documentation for pause

help pause

 PAUSE Wait for user response.
    PAUSE(n) pauses for n seconds before continuing, where n can also be a
    fraction. The resolution of the clock is platform specific. Fractional
    pauses of 0.01 seconds should be supported on most platforms.
 
    PAUSE causes a procedure to stop and wait for the user to strike any
    key before continuing.
 
    NOTE: The maximum pause is 2 seconds for this product offering on this platform.
 
    PAUSE OFF indicates that any subsequent PAUSE or PAUSE(n) commands
    should not actually pause. This allows normally interactive scripts to
    run unattended.
 
    PAUSE ON indicates that subsequent PAUSE commands should pause.
 
    PAUSE QUERY returns the current state of pause, either 'on' or 'off'.
 
    STATE = PAUSE(...) returns the state of pause previous to processing
    the input arguments.
 
    The accuracy of PAUSE is subject to the scheduling resolution of the
    operating system you are using and also to other system activity. It
    cannot be guaranteed with 100% confidence, but only with some expected
    error. For example, experiments have shown that choosing N with a
    resolution of .1 (such as N = 1.7) leads to actual pause values that
    are correct to roughly 10% in the relative error of the fractional
    part. Asking for finer resolutions (such as .01) shows higher relative
    error.
 
    Examples:
        % Pause for 1 seconds
        pause(1)
 
        % Temporarily disable pause
        pause off
        pause(1) % Note that this does not pause
        pause on
 
        % Aternatively, disable/restore the state
        pstate = pause('off')
        pause(1) % Note that this does not pause
        pause(pstate);
 
    See also KEYBOARD, INPUT.

    Documentation for pause
       doc pause

    Other uses of pause

       audioplayer/pause           slrealtime.Target.Stimulation/pause
       parallel-computing/pause

[Ali]

yes, but i dont understand the code concept where i update the location of the time shifted signal using

+[normalised_shift_size 0 0 0]

since i dont know the meaning of the next 2 lines

normalised_shift_size = 2*plot_width/(num_steps-1);

corr_seg_len = length(rxy)/num_steps;

and that part

set(corr_h, 'Ydata', [rxy(1:round(corr_seg_len*k)) ones(1,length(rxy)-round(corr_seg_len*k))*NaN])