Quiver plot - vector direction

Hi,

I am trying to plot quiver plot of 2d data and the generated quiver plot is not pointing in the direction of second dataset (x2,y2) from first dataset (x1,y1). Please let me the error I am committing in displaying the plot.

Thanks,

Vignesh

x1 = [5	5.5	6	6.5	7	7	7	6.5	6	5.5	5	5 5 ];
y1= [5	5	5	5	5	5.5	6	6	6	6	6	5.5 5];
plot (x1,y1)
hold on
xlim([-20 20])
ylim([-20 20])
x2 = [4.19	5.26	6.00	6.74	7.81	7.96	7.81	6.74	6.00	5.26	4.19	4.04 4.19];
y2 = [4.19	4.05	4.08	4.05	4.19	5.50	6.81	6.95	6.92	6.95	6.81	5.50 4.19];
plot(x2,y2)
hold on
quiver(x1,y1,x2,y2)

Answer 1

[Cris LaPierre]

Your U and V values are all positive, so all quivers will point up and to the right.

I think you want U and V to be the difference between 2 and 1, and not the location of 2.

x1 = [5	5.5	6	6.5	7	7	7	6.5	6	5.5	5	5 5 ];
y1= [5	5	5	5	5	5.5	6	6	6	6	6	5.5 5];
plot (x1,y1)
hold on

x2 = [4.19	5.26	6.00	6.74	7.81	7.96	7.81	6.74	6.00	5.26	4.19	4.04 4.19];
y2 = [4.19	4.05	4.08	4.05	4.19	5.50	6.81	6.95	6.92	6.95	6.81	5.50 4.19];
plot(x2,y2)

quiver(x1, y1,x2-x1,y2-y1)

[Vignesh]

Thanks for pointing out the reason why the vectors are not directing as expected.