NcmPowspec

NcmPowspec — Abstrac class for power spectrum implementation.

Properties

gdouble kmax Read / Write / Construct
gdouble kmin Read / Write / Construct
gdouble zf Read / Write / Construct
gdouble zi Read / Write / Construct

Object Hierarchy

    GObject
    ╰── NcmPowspec
        ├── NcPowspecML
        ╰── NcPowspecMNL

Description

This module comprises the set of functions to compute a power spectrum and derived quantities.

Given a field $\delta(\vec{x})$ at position $\vec{x}$, the power spectrum is defined as the Fourier transform of the two-point correlation point, i.e., $$\xi(\vec{x} - \vec{x}^\prime) = \int \frac{d^3 k}{(2 \pi)^3} e^{i \vec{k}.(\vec{x} - \vec{x}^\prime)} P(k),$$ where $\langle \delta(\vec{k} - \vec{k}^\prime)\rangle = (2\pi)^3 \delta_D(\vec{k} - \vec{k}^\prime) P(k)$ and $\delta_D$ is the Dirac's delta function. The standard output is the dimensional power spectrum, not the dimensionless one $\Delta(k)^2$, $$P(k) \equiv \frac{2 \pi^2 \Delta(k)^2}{k^3}.$$

Functions

ncm_powspec_ref ()

NcmPowspec *
ncm_powspec_ref (NcmPowspec *powspec);

Increases the reference count of powspec by one.

Parameters

powspec

a NcmPowspec

 

Returns

powspec .

[transfer full]


ncm_powspec_free ()

void
ncm_powspec_free (NcmPowspec *powspec);

Decreases the reference count of powspec by one.

Parameters

powspec

a NcmPowspec

 

ncm_powspec_clear ()

void
ncm_powspec_clear (NcmPowspec **powspec);

If powspec is different from NULL, decreases the reference count of powspec by one and sets powspec to NULL.

Parameters

powspec

a NcmPowspec

 

ncm_powspec_set_zi ()

void
ncm_powspec_set_zi (NcmPowspec *powspec,
                    const gdouble zi);

Sets the initial redshift $z_i$.

Parameters

powspec

a NcmPowspec

 

zi

initial redshift $z_i$

 

ncm_powspec_set_zf ()

void
ncm_powspec_set_zf (NcmPowspec *powspec,
                    const gdouble zf);

Sets the final redshift $z_f$.

Parameters

powspec

a NcmPowspec

 

zf

final redshift $z_f$

 

ncm_powspec_set_kmin ()

void
ncm_powspec_set_kmin (NcmPowspec *powspec,
                      const gdouble kmin);

Sets the minimum mode value $k_\mathrm{min}$.

Parameters

powspec

a NcmPowspec

 

kmin

minimum mode $k_\mathrm{min}$

 

ncm_powspec_set_kmax ()

void
ncm_powspec_set_kmax (NcmPowspec *powspec,
                      const gdouble kmax);

Sets the maximum mode value $k_\mathrm{max}$.

Parameters

powspec

a NcmPowspec

 

kmax

maxmimum mode $k_\mathrm{max}$

 

ncm_powspec_require_zi ()

void
ncm_powspec_require_zi (NcmPowspec *powspec,
                        const gdouble zi);

Requires the initial redshift to be less or equal to $z_i$.

Parameters

powspec

a NcmPowspec

 

zi

initial redshift $z_i$

 

ncm_powspec_require_zf ()

void
ncm_powspec_require_zf (NcmPowspec *powspec,
                        const gdouble zf);

Requires the final redshift to be greater or equal to $z_f$.

Parameters

powspec

a NcmPowspec

 

zf

final redshift $z_f$

 

ncm_powspec_require_kmin ()

void
ncm_powspec_require_kmin (NcmPowspec *powspec,
                          const gdouble kmin);

Requires the minimum mode value to be less or equal to $k_\mathrm{min}$.

Parameters

powspec

a NcmPowspec

 

kmin

minimum mode $k_\mathrm{min}$

 

ncm_powspec_require_kmax ()

void
ncm_powspec_require_kmax (NcmPowspec *powspec,
                          const gdouble kmax);

Sets the maximum mode value $k_\mathrm{max}$.

Parameters

powspec

a NcmPowspec

 

kmax

maxmimum mode $k_\mathrm{max}$

 

ncm_powspec_get_zi ()

gdouble
ncm_powspec_get_zi (NcmPowspec *powspec);

Gets the initial value $z_i$.

Parameters

powspec

a NcmPowspec

 

ncm_powspec_get_zf ()

gdouble
ncm_powspec_get_zf (NcmPowspec *powspec);

Gets the final value $z_f$.

Parameters

powspec

a NcmPowspec

 

ncm_powspec_get_kmin ()

gdouble
ncm_powspec_get_kmin (NcmPowspec *powspec);

Gets the minimum mode value $k_\mathrm{min}$.

Parameters

powspec

a NcmPowspec

 

ncm_powspec_get_kmax ()

gdouble
ncm_powspec_get_kmax (NcmPowspec *powspec);

Gets the maximum mode value $k_\mathrm{max}$.

Parameters

powspec

a NcmPowspec

 

ncm_powspec_get_nknots ()

void
ncm_powspec_get_nknots (NcmPowspec *powspec,
                        guint *Nz,
                        guint *Nk);

Gets the number of knots used to calculate the power spectrum.

[virtual get_nknots]

Parameters

powspec

a NcmPowspec

 

Nz

number of knots in $z$.

[out]

Nk

number of knots in $k$.

[out]

ncm_powspec_prepare ()

void
ncm_powspec_prepare (NcmPowspec *powspec,
                     NcmModel *model);

Prepares the power spectrum powspec using the model model .

Parameters

powspec

a NcmPowspec

 

model

a NcmModel

 

ncm_powspec_prepare_if_needed ()

void
ncm_powspec_prepare_if_needed (NcmPowspec *powspec,
                               NcmModel *model);

Prepares the object powspec using the model model if it was changed since last preparation.

Parameters

powspec

a NcmPowspec

 

model

a NcmModel

 

ncm_powspec_eval ()

gdouble
ncm_powspec_eval (NcmPowspec *powspec,
                  NcmModel *model,
                  const gdouble z,
                  const gdouble k);

Evaluates the power spectrum powspec at $(z, k)$.

Parameters

powspec

a NcmPowspec

 

model

a NcmModel

 

z

redshift $z$

 

k

mode $k$

 

Returns

$P(z, k)$.


ncm_powspec_eval_vec ()

void
ncm_powspec_eval_vec (NcmPowspec *powspec,
                      NcmModel *model,
                      const gdouble z,
                      NcmVector *k,
                      NcmVector *Pk);

Evaluates the power spectrum powspec at $z$ and in the knots contained in k and puts the result in Pk .

Parameters

powspec

a NcmPowspec

 

model

a NcmModel

 

z

redshift $z$

 

k

a NcmVector

 

Pk

a NcmVector.

[out caller-allocates]

Types and Values

Property Details

The “kmax” property

  “kmax”                     gdouble

Maximum mode value.

Flags: Read / Write / Construct

Allowed values: >= 0

Default value: 1


The “kmin” property

  “kmin”                     gdouble

Minimum mode value.

Flags: Read / Write / Construct

Allowed values: >= 0

Default value: 1e-05


The “zf” property

  “zf”                       gdouble

Final redshift.

Flags: Read / Write / Construct

Allowed values: >= 0

Default value: 1


The “zi” property

  “zi”                       gdouble

Initial redshift.

Flags: Read / Write / Construct

Allowed values: >= 0

Default value: 0