Hi all,
I am looking at ways to determine the sign of an angle between a reference vector (a,b) and any other vector(x,y) of the plane. To do so, I have decided to use the determinant of the matrix: [[a b],[x y]] which equals ax-by. I wanted then to check that the formula works by displaying the plane area which positive and negative signs using the contour_plot.
Here is my question:
Why is the 3rd graph not showing 2 horizontal areas instead of the vertical displayed?
var('x y') f(x,y,a,b)=(ay-bx)/abs(ay-bx) plota1b1=contour_plot(f(x,y,1,1),(-10,10),(-10,10),cmap='jet',colorbar=true) plota0b1=contour_plot(f(x,y,0,1),(-10,10),(-10,10),cmap='jet',colorbar=true) plota1b0=contour_plot(f(x,y,1,0),(-10,10),(-10,10),cmap='jet',colorbar=true) show(plota1b1) show(plota0b1) show(plota1b0)
Thanks