fix_tng_data.py

import requests
import h5py
import yt
print(yt.__version__)

# First download a test halo from the TNG project

baseUrl = 'http://www.tng-project.org/api/'

def get(path, params=None):
    # make HTTP GET request to path
    headers = {"api-key":"0c3c5772a765e2aa23e32cc537b6c315"}
    r = requests.get(path, params=params, headers=headers)

    # raise exception if response code is not HTTP SUCCESS (200)
    r.raise_for_status()

    if r.headers['content-type'] == 'application/json':
        return r.json() # parse json responses automatically

    if 'content-disposition' in r.headers:
        filename = r.headers['content-disposition'].split("filename=")[1]
        with open(filename, 'wb') as f:
            f.write(r.content)
        return filename # return the filename string
    
    return r

id = 100
url = "http://www.tng-project.org/api/Illustris-1/snapshots/z=0/halos/" + str(id) + "/cutout.hdf5"
saved_filename = get(url, params={"gas":"all"})

print(saved_filename)

# Now we have to open up the file we downloaded and fix the header
# in the file to include info yt needs to read this as an Arepo file 

f = h5py.File(saved_filename, "r+")
f["Header"].attrs["NumPart_Total"] = np.array(f["Header"].attrs["NumPart_ThisFile"])
f.create_group("Config")
f["/Config"].attrs["VORONOI"] = 1
f.flush()
f.close()

# Now you can open the file with yt

ds = yt.load(saved_filename)

print(type(ds))

slc = yt.SlicePlot(ds, "z", "density", width=(1.0, "Mpc"), center="max")
slc.save()