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# Directory Listing of Routines

# general/science/spd_mtm/models/pl

- SPD_MTM_PL_FUN
- SPD_MTM_PL_LGLK
- SPD_MTM_PL_NORM
- SPD_MTM_WHT_LGLK

# Routine Descriptions

## SPD_MTM_PL_FUN

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     :Description:
       Power Law (PL) function values at the given frequencies
       with the pl_par parameters.

     :Params:
       INPUTS:
              f - frequency vector
         pl_par - power law parameters:
                  pl_par[0] --> c, constant factor
                  pl_par[1] --> beta, spectral index
       OUTPUTS:
          plfun - 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/pl/spd_mtm_pl_fun.pro)

## SPD_MTM_PL_LGLK

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

     :Params:
       INPUTS:
              pl_par - 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_pl_norm.pro
         spd_mtm_pl_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/pl/spd_mtm_pl_lglk.pro)

## SPD_MTM_PL_NORM

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

     :Params:
       INPUTS:
           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/pl/spd_mtm_pl_norm.pro)

## SPD_MTM_WHT_LGLK

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     :Description:
       Evaluate the log-likelihood of
       the white noise (WHT) PSD model.

     :Params:
       INPUTS:
             wht_par - 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

     :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/pl/spd_mtm_wht_lglk.pro)