Extracting subset of ICs

Matthew Orkney
  • 26 Jan '22


I am interested in tracing the Langragian region of target halos back to the initial conditions. I'd like to do this with TNG50-1, but the initial conditions are a ~300 GB hdf5 file which is a bit beyond my storage capabilities. Is it possible to download a subset of the initial conditions, or even just a particular region?

Thank you and all the best, Matt

Dylan Nelson
  • 26 Jan '22

I'd suggest to sign up for the Lab service, there you can find the IC files and inspect them without downloading.

Although there is not memory available to load 300 GB into memory, you could easily load it e.g. in 100 smaller chunks, to do some processing.

To be honest I do not remember the ordering of this file, although it is probably spatial (Peano-Hilbert curve). Thus you could probably construct a spatial key and use it to load spatial sub-regions, but this is perhaps not so easy.

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