I am trying to rewrite this article:We draw, programming. Machine-generated generation of artistic patterns in vector fields (Russian language) from pseudo-code in Python. I am new to ML, hence the following question arises: How to build a grid of angles and output it through PyCharm? I am at this stage:
import numpy as np
import math
import matplotlib.pyplot as plt
width = 100
height = 100
left_x = int(width * -0.5)
right_x = int(width * 1.5)
top_y = int(height * -0.5)
bottom_y = int(height * 1.5)
resolution = int(width * 0.01)
num_columns = int((right_x - left_x) / resolution)
num_rows = int((bottom_y - top_y) / resolution)
grid=np.ndarray((num_columns, num_rows))
grid[:,:]=math.pi * 0.25
In this code, I create a grid array in which 200 rows and 200 columns, into which the angle 'default_angle' is inserted. Please tell me whether I’m moving in the right direction and how to "draw" a grid, as in an attached link. So far I think I need to use matplotlib.
You need to make several steps to recreate this:
while
out condition
3.3. calculate new position based on angle from starting point
3.4. get new position index --> net new angle
3.5. update starting positionsimport numpy as np import matplotlib.pyplot as plt
size = 50
X = np.arange(1, size, 1)
Y = np.arange(1, size, 1)
U, V = np.meshgrid(X, Y)
# Normalize the arrows:
U = U / np.sqrt(U**2 + V**2)
V = V / np.sqrt(U**2 + V**2)
# create angles field
data = []
for i in np.linspace(0, 180, Y.shape[0]):
data.append([i]*X.shape[0])
angle = np.array(data)
# set starting parameters
x_start_position = 2
y_start_position = 2
step_length = 1.0
point_angle = angle[x_start_position, y_start_position]
line_coordinates = [[x_start_position, y_start_position]]
# collect line points for each step
while x_start_position >= 2:
# calculate tep based on angle
x_step = step_length * np.cos(point_angle*np.pi/180)
y_step = step_length * np.sin(point_angle*np.pi/180)
# calculate new position
x_new_position = x_start_position + x_step
y_new_position = y_start_position + y_step
# get array index of new position
x_new_index = int(x_new_position)
y_new_index = int(y_new_position)
# get new angle
point_angle = angle[y_new_index, x_new_index]
# update start position
x_start_position = x_new_position
y_start_position = y_new_position
# collect results
line_coordinates.append([x_new_position, y_new_position])
# set line coordinates
line_data = np.array(line_coordinates)
x_line = line_data[:,0]
y_line = line_data[:,1]
# plot field
plt.quiver(X, Y, U, V, color='black', angles=angle, width=0.005)
# plot line
plt.plot(x_line, y_line, '-', color='red')
plt.show()
Output: