PyFiNeR: Fitting Near-infrared RR Lyrae light curves

This routine implements the RR Lyrae near-infrared light curve fitting techniques described by Hajdu et al. (2018).

The K-band light curve are fit with the Fourier transformed principal components coefficients; the H-band data is fit with the same light-curve shape; the shape of the J-band light curve is approximated with the K-band principal component amplitudes.

This routine was developed for:

• Python 2.7+ or 3.6+
• Numpy 1.12+
• Scipy 1.0+
• Matplotlib 2.1+

Installation

Copy all files from the bin directory to the same directory in the system PATH. If you get "ImportError: No module named builtins" error while using Python 2.7, install the future package.

Usage

The routine requires six arguments to run; in order, these are:

• COMMENT: a string that is passed printed out in the end; usually the name of the variable; can use quotation marks to carry additional information
• PERIOD: the initial period estimate of the variable
• FILE_K_LC: path of the K light curve file; must exist
• FILE_J_LC: path of the J light curve file; must exist, but can be an empty file
• FILE_H_LC: path of the H light curve file; must exist, but can be an empty file
• OUTPUT.pdf: name of the output pdf file

Given these arguments, the routine does the fit and gives back the following output:

• COMMENT: the string from the argument list
• PERIOD: the final period
• K_MAG: magnitude averaged mean K magnitude
• K_INT: intensity averaged mean K magnitude
• J_MAG_MEAN : magnitude averaged mean J magnitude, calculated with the mean offset
• J_INT_MEAN : intensity averaged mean J magnitude, calculated with the mean offset
• J_MAG_MEDI : magnitude averaged mean J magnitude, calculated with the median offset
• J_INT_MEDI : intensity averaged mean J magnitude, calculated with the median offset
• H_MAG_MEAN : magnitude averaged mean H magnitude, calculated with the mean offset
• H_INT_MEAN : intensity averaged mean H magnitude, calculated with the mean offset
• H_MAG_MEDI : magnitude averaged mean H magnitude, calculated with the median offset
• H_INT_MEDI : intensity averaged mean H magnitude, calculated with the median offset
• U1: amplitude of the first principal component of the K light curve
• U2: amplitude of the second principal component of the K light curve
• U3: amplitude of the third principal component of the K light curve
• U4: amplitude of the fourth principal component of the K light curve
• RMSE: the Root Mean Square Error of the K-band fit
• COST: the final value of the Huber cost function
• COSTN: the Uber cost function per K-band light curve cost
• N_FINAL: the number of K-band light curve points in the final fit
• N_INITIAL: the initial number of K-band light curve points