Drawing a rectangle with special specifications

how can i draw a 172*172 that first edge is black (intensity=0) and second edge 10% brighter and the third edge 10% brighter than second and the last edge 10% brighter than third edge...

thank you for your answers

Answer 1

[Henric Rydén]

figure;
axes('XLim', [-50 200],'YLim', [-50 200]);

line([0 172],[172 172],'LineWidth',5,'Color',[0 0 0])
line([172 172],[172 0],'LineWidth',5,'Color',[.1 .1 .1])
line([172 0],[0 0],'LineWidth',5,'Color',[.2 .2 .2])
line([0 0],[0 172],'LineWidth',5,'Color',[.3 .3 .3])

[Stephen]

corners is not joint together its a problem

[Star Strider]

To compensate for line thickness, change it to:

figure;
axes('XLim', [-50 200],'YLim', [-50 200]);

line([-2 174],[172 172],'LineWidth',5,'Color',[0 0 0])
line([172 172],[174 -2],'LineWidth',5,'Color',[.1 .1 .1])
line([174 -2],[0 0],'LineWidth',5,'Color',[.2 .2 .2])
line([0 0],[-2 174],'LineWidth',5,'Color',[.3 .3 .3])

[Henric Rydén]

If you need nicer corners you should use patch instead of line. The syntax is similar, but you give coordinates of faces and vertices. You can also set transparency of patch objects.