Re: Quiver Matlab function

[Joao Cardoso]

Sara Rainieri wrote:
> 
> I am a neophyte of Octave and I am trying to understand if
> there is any  plot function in octave ambient equivalent to the
> ``quiver.m'' Matllab function.
> This function plots velocity vectors as arrows with component (u,v) at
> the point (x,y):
> quiver(x,y,u,v).
> I tried to execute the quiver.m Matlab file, but it didn't work.
> Thanks
> Sara

Hi, if you have plplot_octave (<http://merlin.inescn.pt/~qual>), then

-- function arrows( X, Y, dx, dy)

# arrows( X, Y, dx, dy)
# plot an array of arrows (partly emulates matlab quiver)
#
# NOTE: preliminary

    of = do_fortran_indexing;do_fortran_indexing=1;
    for i=1:rows(X)*columns(X)
        xx = [X(i); X(i) + dx(i)];
        yy = [Y(i); Y(i) + dy(i)];
        plline(xx,yy);plpoin(X(i) + dx(i),  Y(i) + dy(i), 20);
    endfor
    plflush
    do_fortran_indexing = of;

endfunction


Joao Cardoso                |   e-mail: address@hidden
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