Rose diagram (wind rose)¶
This notebook demonstrates a plot called the rose diagram also known as wind rose or circular histogram.
modelskill.plotting.wind_rose is a stand-alone function, not connected to the Comparer class since it relies on two variables (magnitude and direction) instead of one. It is useful for comparing circular variables such as wind/wave/current directions.
For the example in this notebook, we are using a dataset of modelled and observed waves, which have been pre-processed to a common time axis.
In [1]:
import matplotlib.pyplot as plt
from modelskill.plotting import wind_rose
import mikeio
In [2]:
ds = mikeio.read("../tests/testdata/wave_dir.dfs0")
df = ds[[0,2,1,3]].to_dataframe()
df.head()
Out[2]:
| China_Model: Sign. Wave Height | China_Model: Mean Wave Direction | China_Measured: Sign. Wave Height | China_Measured: Mean Wave Direction | |
|---|---|---|---|---|
| 2006-12-20 22:00:00 | 0.300904 | 320.579071 | 0.251520 | 330.387634 |
| 2006-12-20 23:00:00 | 0.429561 | 316.237732 | 0.228478 | 329.593994 |
| 2006-12-21 00:00:00 | 0.375983 | 316.113342 | 0.201325 | 321.015686 |
| 2006-12-21 01:00:00 | 0.369684 | 315.344604 | 0.183559 | 311.001648 |
| 2006-12-21 02:00:00 | 0.406314 | 313.355347 | 0.175971 | 300.778778 |
In [3]:
wind_rose(df, n_sectors=16);
The most common use case in the frame of skill assessment is to compare two datasets, but the plot can be made with a single dataset as well.
The plot is a matplotlib object, so you can tweak it by adding more information to it.
In [4]:
obs_data = df.iloc[:, [0,1]]
ax = wind_rose(obs_data, mag_step=0.15, labels=["H$_{m0}$ (m)"], cmap1="coolwarm", calm_size=0.08, n_sectors=8);
ax.set_title(f"Some location\n{df.index[0].strftime('%Y-%m-%d')} - {df.index[-1].strftime('%Y-%m-%d')}");
# save to png
# plt.savefig("wind_rose.png")
