"""
Wiggle along tracks
===================

The :meth:`pygmt.Figure.wiggle` method can plot z = f(x,y) anomalies along
tracks. ``x``, ``y``, ``z`` can be specified as 1-D arrays or within a
specified file. The ``scale`` parameter can be used to set the scale of the
anomaly in data/distance units. The positive and/or negative areas can be
filled with color by setting the ``fillpositive`` and/or ``fillnegative``
parameters.
"""

# %%
import numpy as np
import pygmt

# Create (x, y, z) triplets
x = np.arange(-7, 7, 0.1)
y = np.zeros(x.size)
z = 50 * np.exp(-((x / 3) ** 2)) * np.cos(2 * np.pi * x)

fig = pygmt.Figure()
fig.basemap(region=[-8, 12, -1, 1], projection="X10c", frame=["Snlr", "xa2f1"])
fig.wiggle(
    x=x,
    y=y,
    z=z,
    # Set anomaly scale to 20 centimeters
    scale="20c",
    # Fill positive areas red
    fillpositive="red",
    # Fill negative areas gray
    fillnegative="gray",
    # Set the outline width to 1.0 point
    pen="1.0p",
    # Draw a blue track with a width of 0.5 points
    track="0.5p,blue",
    # Plot a vertical scale bar at Middle Right (MR). The bar length (+w)
    # is 100 in data (z) units. Set the z unit label (+l) to "nT".
    position="jMR+w100+lnT",
)
fig.show()