Scatter plot with histograms

To create a scatter plot with histograms at the sides of the plot one can use pygmt.Figure.plot in combination with pygmt.Figure.histogram. The positions of the histograms are plotted by offsetting them from the main scatter plot using pygmt.Figure.shift_origin.

import numpy as np
import pygmt

# Generate random x, y coordinates from a standard normal distribution.
# x values are centered on 0 with a standard deviation of 1, and y values are centered
# on 30 with a standard deviation of 2.
rng = np.random.default_rng()
x = rng.normal(loc=0, scale=1, size=1000)
y = rng.normal(loc=30, scale=2, size=1000)

# Get axis limits from the data limits. Extend the limits by 0.5 to add some margin.
xmin = np.floor(x.min()) - 0.5
xmax = np.ceil(x.max()) + 0.5
ymin = np.floor(y.min()) - 0.5
ymax = np.ceil(y.max()) + 0.5

# Set fill color for symbols and bars.
fill = "seagreen"

# Set the dimensions of the scatter plot.
width, height = 10, 8

fig = pygmt.Figure()
fig.basemap(
    region=[xmin, xmax, ymin, ymax],
    projection=f"X{width}/{height}",
    frame=["WSrt", "af"],
)

# Plot data points as circles with a diameter of 0.15 centimeters and set transparency
# level for all circles to deal with overplotting.
fig.plot(x=x, y=y, style="c0.15c", fill=fill, transparency=50)

# Shift the plot origin and add top margin histogram.
fig.shift_origin(yshift=height + 0.25)

fig.histogram(
    projection=f"X{width}/3",
    frame=["Wsrt", "xf", "yaf+lCounts"],
    # Give the same value for ymin and ymax to have them calculated automatically.
    region=[xmin, xmax, 0, 0],
    data=x,
    fill=fill,
    pen="0.1p,white",
    histtype=0,
    series=0.2,
)

# Shift the plot origin and add right margin histogram.
fig.shift_origin(yshift=-height - 0.25, xshift=width + 0.25)

# Plot the horizontal histogram.
fig.histogram(
    horizontal=True,
    projection=f"X3/{height}",
    # Note that the x- and y-axis are flipped, with the y-axis plotted horizontally.
    frame=["wSrt", "xf", "yaf+lCounts"],
    region=[ymin, ymax, 0, 0],
    data=y,
    fill=fill,
    pen="0.1p,white",
    histtype=0,
    series=0.2,
)
fig.show()