NcmFftlogSBesselJ

NcmFftlogSBesselJ — Logarithm fast fourier transform for a kernel given by the spatial correlation function multipoles.

Properties

guint ell Read / Write / Construct
gdouble q Read / Write / Construct

Object Hierarchy

    GObject
    ╰── NcmFftlog
        ╰── NcmFftlogSBesselJ

Description

This object computes the function (see NcmFftlog) $$Y_n = \int_0^\infty t^{\frac{2\pi i n}{L}} K(t) dt,$$ where the kernel are the spherical bessel function of the first kind $K(t) = t^q j_{\ell}(t)$.

Functions

ncm_fftlog_sbessel_j_new ()

NcmFftlogSBesselJ *
ncm_fftlog_sbessel_j_new (guint ell,
                          gdouble lnr0,
                          gdouble lnk0,
                          gdouble Lk,
                          guint N);

Creates a new fftlog Spherical Bessel J object.

Parameters

ell

Spherical Bessel Integer order

 

lnr0

output center $\ln(r_0)$

 

lnk0

input center $\ln(k_0)$

 

Lk

input/output interval size

 

N

number of knots

 

Returns

a new NcmFftlogSBesselJ.

[transfer full]


ncm_fftlog_sbessel_j_set_ell ()

void
ncm_fftlog_sbessel_j_set_ell (NcmFftlogSBesselJ *fftlog_jl,
                              const guint ell);

ncm_fftlog_sbessel_j_get_ell ()

guint
ncm_fftlog_sbessel_j_get_ell (NcmFftlogSBesselJ *fftlog_jl);

Parameters

fftlog_jl

a NcmFftlogSBesselJ

 

Returns

the current Spherical Bessel integer order $\ell$.


ncm_fftlog_sbessel_j_set_q ()

void
ncm_fftlog_sbessel_j_set_q (NcmFftlogSBesselJ *fftlog_jl,
                            const gdouble q);

ncm_fftlog_sbessel_j_get_q ()

gdouble
ncm_fftlog_sbessel_j_get_q (NcmFftlogSBesselJ *fftlog_jl);

Parameters

fftlog_jl

a NcmFftlogSBesselJ

 

Returns

the current Spherical Bessel power $q$.


ncm_fftlog_sbessel_j_set_best_lnr0 ()

void
ncm_fftlog_sbessel_j_set_best_lnr0 (NcmFftlogSBesselJ *fftlog_jl);

Sets the value of $\ln(r_0)$ which gives the best results for the transformation based on the current value of $\ln(k_0)$, this is based in the rule of thumb $\mathrm{max}_x^*(j_l)$ where $ x^* \approx l + 1$.

Parameters

fftlog_jl

a NcmFftlogSBesselJ

 

ncm_fftlog_sbessel_j_set_best_lnk0 ()

void
ncm_fftlog_sbessel_j_set_best_lnk0 (NcmFftlogSBesselJ *fftlog_jl);

Sets the value of $\ln(k_0)$ which gives the best results for the transformation based on the current value of $\ln(r_0)$, this is based in the rule of thumb $\mathrm{max}_x^*(j_l)$ where $ x^* \approx l+1$.

Parameters

fftlog_jl

a NcmFftlogSBesselJ

 

Types and Values

Property Details

The “ell” property

  “ell”                      guint

Spherical Bessel integer order.

Flags: Read / Write / Construct

Default value: 0


The “q” property

  “q”                        gdouble

Spherical Bessel power.

Flags: Read / Write / Construct

Default value: 0