https://github.com/tboudreaux/PolytropicStellarModel

Simple Polytropic Stellar Model
https://github.com/tboudreaux/PolytropicStellarModel

astrophysics numerical-integration stellar

Last synced: over 1 year ago
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Simple Polytropic Stellar Model

• Host: GitHub
• URL: https://github.com/tboudreaux/PolytropicStellarModel
• Owner: tboudreaux
• Created: 2020-01-21T21:59:18.000Z (over 6 years ago)
• Default Branch: master
• Last Pushed: 2022-09-23T15:23:58.000Z (over 3 years ago)
• Last Synced: 2023-08-13T14:22:25.748Z (almost 3 years ago)
• Topics: astrophysics, numerical-integration, stellar
• Language: TeX
• Homepage:
• Size: 6.54 MB
• Stars: 1
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.txt
  • License: LICENSES

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README

          
Polytrope Project Numerical Integrator

Thomas M. Boudreaux

===================

Compilation Instructions:

	- To compile $ make

	- There are two compile time arguemnts which may be set

		- DATADIR will set where that data files are written to (will make the folder to)

		- PSTANOT will determine if the output is also written to standard output

			- This is in addition to dumping to a dat file which will always happen

			- 0 to supress standard output

			- 1 to print to standard output

		- Examples of use

			- $ make PSTANOT=1 DATADIR=results

				- this will print to standard out and save binaries in a folder called results

			- $ make

				- this will use the default values of PSTANOT=0 and DATADIR=data

Run Time Instructions:

	- there are two executable files, integrate-nonDegenerate and integrate-degenerate

		- running the nonDegenerate file with integrate a polytrope

		- running the degenerate model will integrate a white dwarf model

	- To run $ ./integrate-[non][d/D]generate [n/theta_c] [h] [xi0] [xif] [itr]

  		    n/theta_c[float]       - polytroic index(non degenerate case)/central density (degenerate case)

  		    h[float]       - integration step size

  	 	    xi0[float]     - initial value of xi to start at

  	  	    xif[float]     - value of xi to integrate too

  		    [itr[int]]       - number of terms in power serise to use to approximation theta(xi=Xi0) only used in non degenerate case

Data File Format Specs:

	- After running either executable a file will be saved to whatever data director was spesificed at compile

	  time, by default this is a directory called "data"

		- That file will have the input polytropic index in it along with the either being degenerate or non degenerate

		- The file has a header and a body

			- The header is an set of ASCII key value pairs

			- The body is a byte stream of c++ type doubles

			- The file starts with ">> HEADER"

			- The header continues until the line ">> BODY"

				- After this line the next line is the byte stream

Data View Instructions:

	- To generate graphs of the data:

		- Use the included script 

			- $ python pyUtils/ViewCOutput.py  

			- the script can plot either one data file or multiple

				- If plotting multiple the script can place them all on one figure

				  or break them out into seperate figures

			- Command line options can be shown by running

				- $ python pyUtils.py --help

	- To Get the value of Xi1

		- Use the uncluded script 

			- $ python getXi1.py 

		- Command line options can be shown by running

			- $ python getXi1.py --help

	- If you want to generate the figures of all the dataruns on seperate plots use something like from the pyUtils directory

		- $ ls data/*.dat | awk '{split($0,a,"/"); print a[2]}' | xargs -I{} ./ViewCOutput.py data/{} -o Figures/Multi_{}.pdf

Physical Scaling quantities:

	- To generate the physical scalings from xi, theta, and dtheta use the python script 

		- $ python pyUtils/convertToPhysical.py 

			- use --help to see command line options

	- To plot the physical quantities use the python script 

		- $ python pyUtils/plotPhysical.py  --output 

			- use --help to see command line options

Tests:

	- To test the code use the script 

		- To do this you have to have compiled the integrator and had DATADIR=data (or change the path in the python file in tests)

		- This script will integrate a polytrope of n=1 from 0.00001 to 4 xi with a step size of 0.00001 

		- It will then use an the resultant xi array from that integration to compute the exact solution in the n=1 case

			- sin(xi)/xi

		- Finally it will take the arithmatic mean of the differences

			- Smaller values of the this imply that the integrator is returning a solution close to the exact solution.