how to make a variable take the smallest value

Hello, how could i make a variable in plot take the smallest value and another question how can i set another value of origin .. i want to plot as this figure

and this is my code

    hold on
  if r==0 && w>0
        B=B+w;

      plot(B,A,'k:')
  elseif r==0 && w<0

           B=B+w;

      plot(B,A,'g:')

else
    plot(B,A,'m:')
end
hold off

but here the origin is not the same ( if r==0) and thanks

Answer 1

[Walter Roberson]

What do you mean by "take the smallest value" ? Is the above code being run in a loop and might plot several points close together and you want the result to be coloured according to the color scheme appropriate for the minimum the variable is for each of the samples in the region?

[kimo lassay]

thak you for replying, what i mean when i change the value of "w" for exp. if i take the first time 0.1 and second time 0.2 and other 0.3 i want it to take the value ~0.11or0.15

[Walter Roberson]

How does the 0.11 or 0.15 relate to 0.1, 0.2, 0.3 ?

If you have a list of the w you have used, say in wlist, then

smallest_w = min(wlist);

[kimo lassay]

Thank you very much walter