Why set_param( block, 'Position', pos ) shift subsystems ?

Hi,

I am using this code to resize subsystems in a model :

function format_subsystems( model )

subsystems = find_system(model,'SearchDepth', 1, 'blocktype','SubSystem');
nb_tot = length(subsystems);
for subsystem_index = 1 : 1 : nb_tot
    pos = get_param( subsystems{subsystem_index}, 'Position' );
    nb_ports = get_param( subsystems{subsystem_index}, 'Ports' );
    height = 35 * ( max( nb_ports(1), nb_ports(2)) - 1) + 36 ;
    set_param( subsystems{subsystem_index}, 'Position', [ pos(1), pos(2), pos(1) + 100, pos(2) + height ] );
end
end

Example of result :

pos =

   350    50   450   150

nb_ports =

     1     2     0     0     0     0     0     0

height =

    71

Final subsystem position should be :

     50    50   150   121

But final subsystem position is :

     50    52   150   123

This shift of two pixels is done systematically.

Does anybody can explain me why ? Is there a way to position subsytems as I want ?

Thank you for help.

[Kaustubha Govind]

Bonneuil: If you don't receive a response here, you should probably contact MathWorks Technical Support about this.

Answer 1

[Sohan Lal]

As per my understanding, you are facing the issue of the subsystem getting shifted a few pixels on setting the new position using the set_param function. This is possible with the pixel alignment. When we set the position, internally it tries to make it pixel align, and this might result in a bit of shift in the position.

We can even see this behavior when we manually move the block position, it will still go with the pixel alignment only.