7. Plotting point data#
PolarToolkit also supports some plotting of point data (non-gridded). Here we will download a dataset and make a simple plot.
Import the necessary modules
[1]:
from polartoolkit import fetch, maps, regions
Fetch a pandas dataframe of point measurements of Antarctic geothermal heat flux.
[2]:
df = fetch.ghf(version="burton-johnson-2020", points=True)
df.describe()
[2]:
| lat | lon | top (m) | GHF | Elevation (m.a.s.l.) | x | y | |
|---|---|---|---|---|---|---|---|
| count | 446.000000 | 446.000000 | 152.000000 | 445.000000 | 339.000000 | 4.460000e+02 | 4.460000e+02 |
| mean | -65.597642 | -15.016791 | 13.936974 | 92.180157 | -2508.846608 | -8.626337e+05 | 6.308524e+05 |
| std | 7.374904 | 96.977434 | 41.028407 | 66.437845 | 1565.458501 | 1.865982e+06 | 1.840237e+06 |
| min | -90.000000 | -179.960000 | 0.000000 | -31.000000 | -5401.000000 | -3.771912e+06 | -4.390204e+06 |
| 25% | -72.876425 | -66.667500 | 0.000000 | 54.000000 | -3558.500000 | -2.486918e+06 | -7.412494e+05 |
| 50% | -63.395000 | -48.456350 | 1.910000 | 75.000000 | -3122.000000 | -1.659718e+06 | 1.122676e+06 |
| 75% | -61.843300 | 60.120825 | 6.000000 | 112.000000 | -846.000000 | 3.824856e+05 | 2.009383e+06 |
| max | -50.200000 | 179.966700 | 260.000000 | 626.000000 | 349.000000 | 4.304154e+06 | 4.294868e+06 |
Use the basemap function to make a figure instance, and add the points to that.
[3]:
fig = maps.basemap(
region=regions.victoria_land,
title="Geothermal Heat Flux",
imagery_basemap=True,
imagery_transparency=50,
coast=True,
hemisphere="south",
points=df,
points_cmap="magma",
points_fill="GHF",
points_pen=".2p,black",
colorbar=True,
hist=True,
hist_bin_num=15,
cbar_label="mW/m@+2@+",
)
fig.show(dpi=200)
grdimage [WARNING]: (w - x_min) must equal (NX + eps) * x_inc), where NX is an integer and |eps| <= 0.0001.
grdimage [WARNING]: w reset from 100000 to 99766.1470198
grdimage [WARNING]: (e - x_min) must equal (NX + eps) * x_inc), where NX is an integer and |eps| <= 0.0001.
grdimage [WARNING]: e reset from 1000000 to 1000045.54542
grdimage [WARNING]: (s - y_min) must equal (NY + eps) * y_inc), where NY is an integer and |eps| <= 0.0001.
grdimage [WARNING]: s reset from -2200000 to -2200065.03982
grdimage [WARNING]: (n - y_min) must equal (NY + eps) * y_inc), where NY is an integer and |eps| <= 0.0001.
grdimage [WARNING]: n reset from -1000000 to -999825.037242
