Create an angle between two vectors vpython?

Question

I am trying to create an angle symbol using vpython between two vectors. These vectors are the source vector and the x-y projection of this vector. I am using the vpython package and particularly arc from the shapes module of vpython.

from vpython import *
import numpy as nump


scene2 = canvas(title='Source Vector',
     width=800, height=600,
     center=vector(0,0,0), background=color.white)

scene2.select()

geophone = pyramid(pos=vector(0,0,0), size=vector(2,2,2),
                  color = color.green, up = vector(-1,0,0))

shot_loc = sphere(pos=vector(-20,30,-20), 
                size=vector(2,2,2), color= color.red)

shot_loc_label = label(pos=shot_loc.pos,
    text='Vib Shot', xoffset=-30,
    yoffset=30, space=10,
    height=12, 
    font='serif')

ray_vector = arrow(pos=vector(0,0,0),  axis=shot_loc.pos,
                   shaftwidth=0.2, color= color.blue, length  =40, headlength = 2, headwidth =1)

ray_vec_label = label(pos=(ray_vector.axis - ray_vector.pos)/2,
    text='Ray Vector', xoffset=-30,
    yoffset=30, space=10,
    height=12, 
    font='sans')

source_vector = arrow(pos=vector(0,0,0),  axis= vector(20,-30, 20),
                   shaftwidth=0.2, color= color.red, length  =30, headlength = 2, headwidth =1)

projection_of_source_vector = cylinder(pos=vector(0,0,0),  axis= vector(20,0, 20),
                   radius=0.2, color=color.green)

source_vec_label = label(pos=source_vector.axis,
    text='Source Vector', xoffset=30,
    yoffset=30, space=10,
    height=12, 
    font='sans')





plunge_angle = diff_angle(vector(20,0, 20),vector(20,-30, 20))

plung_arc = shapes.circle(radius=10, angle1=0, angle2=plunge_angle, np=10, rotate=90)



extrusion(path=[vector(20,0, 20), vector(20,-30, 20)], 
          shape=plung_arc)


x_axis = arrow(pos=vector(-50,0,0),  axis=vector(50,0,0), shaftwidth=0.2,
               color= color.black, length  =100, headlength = 2, headwidth =1)

z_axis = arrow(pos=vector(0,-40,0),  axis=vector(0,40,0), shaftwidth=0.2,
               color= color.black, length  =80, headlength = 2, headwidth =1)

y_axis = arrow(pos=vector(0,0,40),  axis=vector(0,0,-40), shaftwidth=0.2,
               color= color.black, length  =80, headlength = 3, headwidth =2)



T_x = text(text='X',
     align='center', color=color.black, pos = vector(-52,0,0), 
           billboard =True, height =2)

T_y = text(text='Z',
     align='center', color=color.black, pos = vector(0,-43,0),
           billboard =True, height =2)

T_z = text(text='Y',
     align='center', color=color.black, pos = vector(0,0, 43),
           billboard =True, height =2)

T_x.width = 2*T_x.width
T_y.width = 2*T_y.width
T_z.width = 2*T_z.width

3d cartisian

Answer 1

Finally managed to make it myself. The result of this code written in jupyter notebook is shown in the accompanying figure. I am using vpython new version which can run in jupyter notebook.

One this could not be accomplished is writing theta and alpha using Latex.

from vpython import *
import numpy as nump


scene2 = canvas(width=800, height=600,
     center=vector(0,0,0), background=color.white)

scene2.select()

geophone = pyramid(pos=vector(0,0,0), size=vector(2,2,2),
                  color = color.green, up = vector(-1,0,0))

geophone_label = label(pos=geophone.pos,
    text='Geophone', xoffset=-30,
    yoffset=-20, space=10,
    height=12, 
    font='sans')

shot_loc = sphere(pos=vector(-20,30,-20), 
                size=vector(2,2,2), color= color.red)

shot_loc_label = label(pos=shot_loc.pos,
    text='Vib Shot', xoffset=-30,
    yoffset=30, space=10,
    height=12, 
    font='sans')

ray_vector = arrow(pos=vector(0,0,0),  axis=shot_loc.pos,
                   shaftwidth=0.2, color= color.blue, length  =40, headlength = 2,
                   headwidth =1)

ray_vec_label = label(pos=(ray_vector.axis - ray_vector.pos)/2,
    text='Ray Vector', xoffset=-30,
    yoffset=30, space=10,
    height=12, 
    font='sans')

source_vector = arrow(pos=vector(0,0,0),  axis= vector(20,-30, 20),
                   shaftwidth=0.2, color= color.red, length  =30, headlength = 2,
                      headwidth =1)

projection_of_source_vector = cylinder(pos=vector(0,0,0),  axis= vector(20,0, 20),
                   radius=0.2, color=color.green)

source_vec_label = label(pos=source_vector.axis,
    text='Source Vector', xoffset=30,
    yoffset=30, space=10,
    height=12, 
    font='sans')




plunge_angle = diff_angle(vector(20,0, 20),vector(20,-30, 20))

plung_arc = shapes.arc(radius=10, angle1=0, angle2=-plunge_angle)

b = cross(vector(20,0, 20),vector(20,-30, 20))
norm_vector = norm(b)

extrusion(path=[vector(0,0, 0), norm_vector], 
          shape=plung_arc)

plunge_label = label(pos=vector(4,-4,4),
    text='α', xoffset=30,
    yoffset=-20, space=10,
    height=12, 
    font='sans')



back_azimuth_angle = diff_angle(vector(20,0, 20),vector(0,0, -1))
back_azimuth_arc = shapes.arc(radius=10, angle1=0, angle2=back_azimuth_angle)

c = cross(vector(20,0, 20),vector(0,0, -1))
norm_vector_azimth = norm(c)

extrusion(path=[vector(0,0, 0), norm_vector_azimth], 
          shape=back_azimuth_arc)

azimuth_label = label(pos=vector(3,0,-2),
    text='θ', xoffset=30,
    yoffset=30, space=10,
    height=12, 
    font='sans')


x_axis = arrow(pos=vector(-50,0,0),  axis=vector(50,0,0), shaftwidth=0.2,
               color= color.black, length  =100, headlength = 2, headwidth =1)

z_axis = arrow(pos=vector(0,-40,0),  axis=vector(0,40,0), shaftwidth=0.2,
               color= color.black, length  =80, headlength = 2, headwidth =1)

y_axis = arrow(pos=vector(0,0,40),  axis=vector(0,0,-40), shaftwidth=0.2,
               color= color.black, length  =80, headlength = 3, headwidth =1)



T_x = text(text='X',
     align='center', color=color.black, pos = vector(-52,0,0), 
           billboard =True, height =2)

T_y = text(text='Z',
     align='center', color=color.black, pos = vector(0,-43,0),
           billboard =True, height =2)

T_z = text(text='Y',
     align='center', color=color.black, pos = vector(0,0, 43),
           billboard =True, height =2)

T_x.width = 2*T_x.width
T_y.width = 2*T_y.width
T_z.width = 2*T_z.width