Defining aerofoil databases

Here is an example of how to save aerofoil data into the npz file format expected by bemused.AerofoilDatabase. Of course, you can load the data from another source rather than embedding directly in a Python script.

import numpy as np

adata = {}

# Add data for different thicknesses. For example, 100% thickness is easy...
# The three columns are Cl, Cd and Cm

adata[100] = """
-180.00      0.000   0.500   0.000
0.00 0.000   0.500   0.000
180.00       0.000   0.500   0.000
"""

# Add other data for other thicknesses...

def parseData(s):
    a = np.array([tuple(map(float, row.split('\t'))) for row in s.strip().split('\n')],
                 dtype=[('alpha', float), ('CL', float), ('CD', float), ('CM', float)])
    a['alpha'] *= pi/180
    return a

parsed_adata = {k: parseData(v) for k, v in adata.items()}

# Save the aerofoil data
keys = sorted(parsed_adata.keys())
np.savez('aerofoils.npz',
         thicknesses=[float(k) / 100  for k in keys],
         datasets   =[parsed_adata[k] for k in keys])