python - Scipy RegularGridInterpolator 转动插值向量场

Question

任务：

我正在尝试在常规网格上插入矢量场，即：

问题：

我正在使用scipy的 RegularGridInterpolator 来执行此操作。然而，似乎得到的向量场相对于原始向量场发生了变化：

有谁知道为什么？

重现示例的 Python 代码：

from scipy.interpolate import RegularGridInterpolator
import matplotlib.pyplot as plt
import numpy as np

# ORIGINAL 
# Number of points (NxN)
N = 50
# Boundaries
ymin = -2.; ymax = 2.
xmin = -2.; xmax = 2.
# Create Meshgrid
x = np.linspace(xmin,xmax, N)
y = np.linspace(ymin,ymax, N)
xx, yy = np.meshgrid(x, y)
# Vector Field
Fx  = np.cos(xx + 2*yy)
Fy  = np.sin(xx - 2*yy)
# Plot vector field
fig, ax = plt.subplots()
ax.quiver(x, y, Fx, Fy)
plt.title("Original")
plt.show()

# REDUCED 
# Number of points (NxN)
N = 10
# Boundaries
ymin = -2.; ymax = 2.
xmin = -2.; xmax = 2.
# Create Meshgrid
x = np.linspace(xmin,xmax, N)
y = np.linspace(ymin,ymax, N)
xx, yy = np.meshgrid(x, y)
# Vector Field
Fx  = np.cos(xx + 2*yy)
Fy  = np.sin(xx - 2*yy)
# Plot vector field
fig, ax = plt.subplots()
ax.quiver(x, y, Fx, Fy)
plt.title("Reduced")
plt.show()

# INTERPOLATED VERSION BASED ON REDUCED

# Iterpolate
my_interpolating_function_x = RegularGridInterpolator((x, y), Fx)
my_interpolating_function_y = RegularGridInterpolator((x, y), Fy)
# Create Meshgrid
N = 50
x = np.linspace(xmin,xmax, N)
y = np.linspace(ymin,ymax, N)
grid = np.meshgrid(x, y)
new_points = np.vstack(list(map(np.ravel, grid))).T
# Interpolate
F_x_inter = my_interpolating_function_x(new_points)
F_y_inter = my_interpolating_function_y(new_points)
# reshape
F_x_inter = np.reshape(F_x_inter,(50,50))
F_y_inter = np.reshape(F_y_inter,(50,50))
#plot
fig, ax = plt.subplots()
ax.quiver(x, y, F_x_inter, F_y_inter)
plt.title("Interpolated")
plt.show()

标签： pythonvectorscipyfield