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Functions
Types and Values
#define | NC_SCALEFACTOR_DEFAULT_ZF |
#define | NC_SCALEFACTOR_DEFAULT_A0 |
#define | NC_SCALEFACTOR_DEFAULT_RELTOL |
#define | NC_SCALEFACTOR_DEFAULT_ABSTOL |
#define | NC_SCALEFACTOR_OMEGA_K_ZERO |
#define | NC_SCALEFACTOR_MIN_ETA_STEP |
Description
Integrates the first order Friedmann equation,
$$E^2 = \frac{\rho}{\rho_{\mathrm{crit}0}} + \Omega_{k0} x^2.$$ Where
${\mathrm{crit}0}$ is the critical density today [nc_hicosmo_crit_density()
],
$E = H / H_0$ is the dimensionless Hubble function [nc_hicosmo_E()
]
and $\Omega_{k0}$ is the curvature parameter today [nc_hicosmo_Omega_k0()
].
Functions
nc_scalefactor_new ()
NcScalefactor * nc_scalefactor_new (const gdouble zf
,NcDistance *dist
);
Creates a new NcScalefactor valid for calculations in the $[0, z_f]$ interval.
nc_scalefactor_ref ()
NcScalefactor *
nc_scalefactor_ref (NcScalefactor *a
);
Increases the reference count of a
by one.
nc_scalefactor_free ()
void
nc_scalefactor_free (NcScalefactor *a
);
Decreases the reference count of a
by one.
nc_scalefactor_clear ()
void
nc_scalefactor_clear (NcScalefactor **a
);
If *a
is different from NULL, decreases the reference
count of *a
by one and sets *a
to NULL.
nc_scalefactor_prepare_if_needed ()
void nc_scalefactor_prepare_if_needed (NcScalefactor *a
,NcHICosmo *cosmo
);
FIXME
nc_scalefactor_set_zf ()
void nc_scalefactor_set_zf (NcScalefactor *a
,const gdouble zf
);
Sets the final redshift of the integration.
nc_scalefactor_set_a0 ()
void nc_scalefactor_set_a0 (NcScalefactor *a
,const gdouble a0
);
Sets the value of the scale factor today.
nc_scalefactor_set_reltol ()
void nc_scalefactor_set_reltol (NcScalefactor *a
,const gdouble reltol
);
Sets the relative tolerance of the integration.
nc_scalefactor_set_abstol ()
void nc_scalefactor_set_abstol (NcScalefactor *a
,const gdouble abstol
);
Sets the absolute tolerance of the integration.
nc_scalefactor_set_a0_conformal_normal ()
void nc_scalefactor_set_a0_conformal_normal (NcScalefactor *a
,gboolean enable
);
When enable
is TRUE, it sets the value of the scale factor
today $a_0$, assuming that the conformal hypersurface
the spatial hypersurface where ($a=1$) hascurvature
equals to 1Mpc, i.e., $1/\sqrt{K} = 1\,\mathrm{Mpc}$.
If enable
is FALSE it lets $a_0$ untouched. *
nc_scalefactor_get_zf ()
gdouble
nc_scalefactor_get_zf (NcScalefactor *a
);
Gets the current final redshift $z_f$.
nc_scalefactor_get_a0 ()
gdouble
nc_scalefactor_get_a0 (NcScalefactor *a
);
Gets the current value of the scale factor today $a_0$.
nc_scalefactor_get_reltol ()
gdouble
nc_scalefactor_get_reltol (NcScalefactor *a
);
Gets the current relative tolerance.
nc_scalefactor_get_abstol ()
gdouble
nc_scalefactor_get_abstol (NcScalefactor *a
);
Gets the current absolute tolerance.
nc_scalefactor_eval_z_eta ()
gdouble nc_scalefactor_eval_z_eta (NcScalefactor *a
,const gdouble eta
);
Calculates the value of the redshift in $\eta$, i.e., $z(\eta)$.
nc_scalefactor_eval_a_eta ()
gdouble nc_scalefactor_eval_a_eta (NcScalefactor *a
,const gdouble eta
);
Calculates the value of the scale factor in $\eta$, i.e., $a(\eta)$.
nc_scalefactor_eval_eta_z ()
gdouble nc_scalefactor_eval_eta_z (NcScalefactor *a
,const gdouble z
);
Calculates the value of the conformal time at $z$, i.e., $\eta(z)$.
nc_scalefactor_eval_eta_x ()
gdouble nc_scalefactor_eval_eta_x (NcScalefactor *a
,const gdouble x
);
Calculates the value of the conformal time at $x$, i.e., $\eta(z(x))$.
nc_scalefactor_eval_t_eta ()
gdouble nc_scalefactor_eval_t_eta (NcScalefactor *a
,const gdouble eta
);
Calculates the value of the cosmic time at $\eta$, i.e., $t(\eta)$.
nc_scalefactor_eval_eta_t ()
gdouble nc_scalefactor_eval_eta_t (NcScalefactor *a
,const gdouble t
);
Calculates the value of the conformal time at $t$, i.e., $\eta(t)$.
Property Details
The “a0”
property
“a0” gdouble
Scale factor today a_0.
Flags: Read / Write / Construct
Allowed values: >= 0
Default value: 1
The “a0-conformal-normal”
property
“a0-conformal-normal” gboolean
Scale factor today a_0 from normalized curvature radius.
Flags: Read / Write / Construct
Default value: FALSE
The “abstol”
property
“abstol” gdouble
Absolute tolerance.
Flags: Read / Write / Construct
Allowed values: >= 0
Default value: 0
The “reltol”
property
“reltol” gdouble
Relative tolerance.
Flags: Read / Write / Construct
Allowed values: [0,1]
Default value: 1e-13
The “zf”
property
“zf” gdouble
Initial redshift.
Flags: Read / Write / Construct
Allowed values: >= 0
Default value: 1e+14