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# Directory Listing of Routines

# general/science/spd_mtm/models/bpl

- SPD_MTM_BPL_FUN
- SPD_MTM_BPL_LGLK
- SPD_MTM_BPL_NORM

# Routine Descriptions

## SPD_MTM_BPL_FUN

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     :Description:
       Bending Power Law (BPL) function values at the given frequencies
       with the bpl_par parameters.

     :Params:
       INPUTS:
               f - frequency vector
         bpl_par - bending power law parameters:
                   bpl_par[0] --> c, constant factor
                   bpl_par[1] --> beta, spectral index
                   bpl_par[2] --> gamma, spectral index
                   bpl_par[3] --> fb, frequency break
       OUTPUTS:
          bplfun - bending power law function

     :Author:
         Simone Di Matteo, Ph.D.
         8800 Greenbelt Rd
         Greenbelt, MD 20771 USA
         E-mail: simone.dimatteo@nasa.gov

(See general/science/spd_mtm/models/bpl/spd_mtm_bpl_fun.pro)

## SPD_MTM_BPL_LGLK

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     :Description:
       Evaluate the log-likelihood of
       the bending power law (BPL) PSD model.

     :Params:
       INPUTS:
             bpl_par - bending power law PSD parameters

       OUTPUTS:
                   M - log-likelihood

       COMMON VARIABLES:
         max_lklh
              psd_ml - PSD for the maximum likelihood model fit
               ff_ml - frequency vector for the maximum likelihood model fit
            alpha_ml - half degree of freedom of the PSD at each frequency

     :Uses:
         spd_mtm_bpl_norm.pro
         spd_mtm_bpl_fun.pro

     :Author:
         Simone Di Matteo, Ph.D.
         8800 Greenbelt Rd
         Greenbelt, MD 20771 USA
         E-mail: simone.dimatteo@nasa.gov

(See general/science/spd_mtm/models/bpl/spd_mtm_bpl_lglk.pro)

## SPD_MTM_BPL_NORM

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     :Description:
       Constant normalization factor for the BPL model estimated with
       the maximum likelihood theoretical solution.

     :Params:
       INPUTS:
              ff - Fourier frequencies vector
         bpl_par - bending power law parameters:
                   bpl_par[0] --> beta, spectral index
                   bpl_par[1] --> gamma, spectral index
                   bpl_par[2] --> fb, frequency break

             bet - spectral index
              ff - Fourier frequencies vector
             psd - power spectral density
           alpha - half degree of freedom of Smtm for each frequency

       OUTPUTS:
               c - constant factor

     :Author:
         Simone Di Matteo, Ph.D.
         8800 Greenbelt Rd
         Greenbelt, MD 20771 USA
         E-mail: simone.dimatteo@nasa.gov

(See general/science/spd_mtm/models/bpl/spd_mtm_bpl_norm.pro)