HOw can I change the size of the arrows

I did this code to plot a vector field, and i was wondering how can i change the size of the arrows?

 t1 = linspace(-1,100,20);
y1 = linspace(-1,150,20);
[T,Y]=meshgrid(t1,y1);
DY=TribMod1(T,Y); DT=ones(size(DY));
scale =  1./sqrt(DT.^2+DY.^2);
quiver(T,Y, scale.*DT, scale.*DY);
axis([-1 100 -1 151])
ylabel('y')
xlabel('time (t)')
title('Direction field of function(1) with b=0.005')

Answer 1

[Star Strider]

Use the 'AutoScaleFactor' property:

% CREATE DATA: 
a = linspace(0,6*pi);
x = exp(-0.1*a) .* cos(a);
y = exp(-0.1*a) .* sin(a);
da = diff([0 a]);
dxda = diff([0 x]) ./ da;
dyda = diff([0 y]) ./ da;

% PLOT: 
figure(1)
subplot(2,1,1)
h1 = quiver(x, y, dxda, dyda)
set(h1,'AutoScale','on', 'AutoScaleFactor', 2)
axis equal square
title('Arrows 2')
subplot(2,1,2)
h2 = quiver(x, y, dxda, dyda)
set(h2,'AutoScale','on', 'AutoScaleFactor',0.5)
axis equal square
title('Arrows ½')

produces:

[Cola]

How about the size of the arrows in streamslice. Thanks.

Answer 2

[Geoff Hayes]

From your code, grab the quivergroup handle that is returned from the quiver function

 h = quiver(T,Y, scale.*DT, scale.*DY);

You can change the size (width) of the arrows from its default value of 0.5 as follows

 set(h,'LineWidth',2)

Note that you could also do this at the line quiver(T,Y, scale.*DT, scale.*DY,'LineWidth',2);.

Try this and see what happens!