## Why is the size of the function different in plot3 and quiver3?

### physics scientist (view profile)

on 20 Sep 2017
Latest activity Commented on by Chad Greene

on 20 Sep 2017

f = 10^8;
x = 0:0.1:5;
c=3*10^8;
z =sin(2*pi*x*f/c+f*x/c);
y =sin(2*pi*x*f/c+f*x/c+pi/2);
o = zeros(size(x));
quiver3(x,o,o,o,z,o,'LineStyle','--');
hold on
quiver3(x,o,o,o,o,y,'LineStyle','--')
hold on
quiver3(x,o,o,o,z,y,'LineStyle','-')
hold on
plot3(x,z,o)
hold on
plot3(x,o,y)
hold on
plot3(x,z,y)
axis square
output:

### Tags

on 20 Sep 2017

on 20 Sep 2017

The quiver and quiver3 functions automatically scale the vectors. To turn off automatic scaling, add a 0 just before setting the 'LineStyle'. That is,
quiver3(x,o,o,o,z,o,0,'LineStyle','--');
hold on
quiver3(x,o,o,o,o,y,0,'LineStyle','--')
quiver3(x,o,o,o,z,y,0,'LineStyle','-')

on 20 Sep 2017
Also a small note: You only need to say hold on once, and the hold will stay on for that plot until you say hold off.
physics scientist

### physics scientist (view profile)

on 20 Sep 2017
Thank you! I have one more problem the all the axes are in different scales i.e. lets say z axis shows 2 units while y axis shows 6 units so they should be shown equal in length on screen but here they are equal, is there any way to show them with the size proportional to their values?