[Bug]: Hexbin gridsize interpreted differently for x and y #21349
Description
Bug summary
gridsize results in 2x the expected number of elements in y-direction
Code for reproduction
import matplotlib.pyplot as plt
import numpy as np
np.random.seed(19680801)
n = 100000
x = np.random.standard_normal(n)
y = 2.0 + 3.0 * x + 4.0 * np.random.standard_normal(n)
fig, ax = plt.subplots(figsize=(6, 6))
h = ax.hexbin(x, y, gridsize=(10, 10), marginals=True, reduce_C_function=np.sum)Actual outcome
Expected outcome
This image was taken with gridsize=(10, 5) but should be the result of gridsize=(10, 10).