File formats

Format of a file with a list of models and properties:

Description:

  • The first three lines are a header. They specify the values of the all_params, all_params_latex, and grid_params variables which provide a list of the parameters provided in the file, a latex version of the parameter names, and a list of the parameters which characterise the evolutionary tracks, respectively. These variables should be specified in python format following a hash. Optional comments may be included at the end, following another hash symbol. The parameters Age_adim and Age should be included in all_params and excluded from grid_params.

  • The following section is a large table of values. Each line corresponds to one model in the grid and each column to one of the model parameters as specified in the first two lines of the header.

  • Except for the first three lines, the order of the lines does not matter. SPInS will construct evolutionary tracks based on the parameters in the grid_params variable, and sort them according to the age parameter (Age_adim). Furthermore, the order of the columns does not matter as long as they are coordinated with the all_params and all_params_latex variables.

Example:

Here’s an example of a file read by SPInS (via the model.Model_grid.read_model_list() method):

# ['Age_adim', 'Age', 'Mass0', 'Luminosity', 'Teff', 'Radius', 'MoH'] # all_params
# [r'Age parameter, $\tau$', r'Age, $t$ (Myrs)', r'Initial mass, $M_0/M_{\odot}$', r'Luminosity, $L/L_{\odot}$', r'Effective temperature, $T_{\mathrm{eff}}$',r'Radius, $R/R_{\odot}$', r'Metallicity, $\mathrm{[M/H]}$'] # all_params_latex
# ['Mass0','MoH'] # grid_params
0.00000e+00 1.00000e-15 6.00000e-01 6.66239e-02 4.00654e+03 5.36736e-01 2.54000e-01
5.00000e-04 1.79472e+02 6.00000e-01 6.66515e-02 4.00654e+03 5.36847e-01 2.54000e-01
1.00000e-03 3.58944e+02 6.00000e-01 6.66776e-02 4.00654e+03 5.36952e-01 2.54000e-01
1.50000e-03 5.38417e+02 6.00000e-01 6.67052e-02 4.00654e+03 5.37064e-01 2.54000e-01
2.00000e-03 7.17889e+02 6.00000e-01 6.67314e-02 4.00654e+03 5.37169e-01 2.54000e-01

This grid contains 5 models. The first column contains the dimensionless age, the second the physical age (in Myrs), the third the initial mass, and so forth.

Format of a file with observational constraints:

Description:

  • a collection of lines with classic constraints. These start with the name of the relevant variable (the list of available variables is given by the all_params variable of the grid, as specified in the header of the file with the list of model properties). Various elementary functions can be applied to the variables by including the appropriate prefix in the name. This is then followed by a description of its probability distribution function. This probability distribution function is specified in two possible ways:

    • it is implicitly assumed to be Gaussian. In this situation it is only necessary to specify the mean value and the one sigma error bar. For example:

      Teff 6100 80

    • it is explicitly specified (different options are given in SPInS.Distribution):

      Teff Uniform 6000 6200

  • anything following a # is a comment

  • the order of the lines does not matter

Example:

Teff         5283    44      # this is a (useless) comment
log_Luminosity -0.303 0.011  # a variable with a function applied to it
MoH Uniform  -0.39  -0.33    # a non-Gaussian distribution