Add functions to read initial values from file

[mkruckow]

Add the functionality to be able to read the initial binary values from a given file.

• [x] add a field to the population_params_default.ini to take a file name, if empty data will be randomly generated as before
• [x] add function to read the file
  • try to infer the name a value may have in the file otherwise take a random sample of the same length as the file provides
  • extend the population in the file by doubling it, if needed
  • read kick values additionally to initial values
• [x] sort POSYDON errors and add description of python standard ones
• [x] tested with ZAMS_values.csv, see below

ZAMS_values.csv content:

M_1,M_2,P_orb,e,w1,phi1,theta1,s1_natal_kick_array_3 10.0,10.0,10.0,0.0,0.0,0.0,0.0,0.0 10.0,10.0,100.0,0.0,1.0,0.0,0.0,0.0 10.0,10.0,1000.0,0.0,10.0,0.0,0.0,0.0 20.0,10.0,10.0,0.0,10.0,0.785398163,0.0,0.0 20.0,10.0,100.0,0.0,10.0,1.570796327,0.0,0.0 20.0,10.0,1000.0,0.0,10.0,2.35619449,0.0,0.0 40.0,10.0,10.0,0.0,10.0,3.141592654,0.0,0.0 40.0,10.0,100.0,0.0,10.0,0.785398163,0.785398163,0.0 40.0,10.0,1000.0,0.0,10.0,1.570796327,0.785398163,0.0 20.0,20.0,10.0,0.0,10.0,2.35619449,0.785398163,0.0 20.0,20.0,100.0,0.0,10.0,3.141592654,0.785398163,0.0 20.0,20.0,1000.0,0.0,10.0,0.785398163,0.785398163,0.785398163 40.0,20.0,10.0,0.0,10.0,1.570796327,0.785398163,0.785398163 40.0,20.0,100.0,0.0,10.0,2.35619449,0.785398163,0.785398163 40.0,20.0,1000.0,0.0,10.0,3.141592654,0.785398163,0.785398163 40.0,40.0,10.0,0.0,10.0,4.712388981,0.785398163,0.785398163 40.0,40.0,100.0,0.0,10.0,4.712388981,0.785398163,1.570796327 40.0,40.0,1000.0,0.0,10.0,4.712388981,0.785398163,4.712388981

[astroJeff]

To clean up the input string options, can we use either .lower() or .casefold(), see SO link: https://stackoverflow.com/questions/319426/how-do-i-do-a-case-insensitive-string-comparison

[mkruckow]

To clean up the input string options, can we use either .lower() or .casefold(), see SO link: https://stackoverflow.com/questions/319426/how-do-i-do-a-case-insensitive-string-comparison

I have made the change to use those functions to shorten the lists. Should we get an own function, which removes dashes, underscores and spaces to shorten it even more?

[maxbriel]

A bit late to this PR, but this functionality is already there in the binarypopulation.py, where you can read and evolve binaries from an hdf5 file. That function is not optimised for reading the binaries from the file, but works correctly in evolving the binaries using custom initial ZAMS value.

I'm not sure what the added benefit of two frameworks for the same thing is. Is it possible to combine the two in some way or is there additional functionality here that is missing in the other?

[mkruckow]

A bit late to this PR, but this functionality is already there in the binarypopulation.py, where you can read and evolve binaries from an hdf5 file. That function is not optimised for reading the binaries from the file, but works correctly in evolving the binaries using custom initial ZAMS value.

I'm not sure what the added benefit of two frameworks for the same thing is. Is it possible to combine the two in some way or is there additional functionality here that is missing in the other?

The from_hdf function is aimed to read in from an existing population file. Usually, you'd even use it to read in the evolution not just ZAMS values. Any hdf5 file read by this function needs to be formatted in the POSYDON way, hence having all columns named as POSYDON would name them. Additionally, I'm not sure whether it will work well, if the load is specified in the population_params.ini (surely the default version doesn't include value, which you'd need to change). Using the from_hdf at least requires a two step process from a user.

So, additional functionality here is:

• read from a simpler file
• flexibly detect column names
• easy to use in population_params.ini
• it has a fallback to the POSYDON functions for non given values
• it allows to take less or more binaries than specified (this allows to get a subpopulation or simulate the same binary but with different kicks several times with and without setting them externally)

Additional functionality of from_hdf:

• read any amount of the evolution (more than initial values)

[mkruckow]

@maxbriel, maybe we can add the option to switch to the from_hdf in case the given file has an h5 file extension in an new PR?