Gyoto::Metric::Python Class Reference

Metric coded in Python. More...

#include <GyotoPython.h>

Inheritance diagram for Gyoto::Metric::Python:
Gyoto::Metric::Generic Gyoto::Python::Base Gyoto::SmartPointee Gyoto::Object Gyoto::Hook::Teller

List of all members.

Public Types

typedef Gyoto::SmartPointer
< Gyoto::SmartPointee
Subcontractor_t (Gyoto::FactoryMessenger *, std::vector< std::string > const &)
 A subcontractor builds an object upon order from the Factory.

Public Member Functions

virtual Property const * getProperties () const
 Get list of properties.
 Python (const Python &)
virtual Pythonclone () const
 Virtual copy constructor.
void spherical (bool)
bool spherical () const
virtual std::string module () const
 Return module_.
virtual void module (const std::string &)
 Set module_ and import the Python module.
virtual std::string inlineModule () const
 Return inline_module_.
virtual void inlineModule (const std::string &)
 Set inline_module_ and import the Python module.
virtual std::string klass () const
 Retrieve class_.
virtual void klass (const std::string &)
 Set class_ and instantiate the Python class.
virtual std::vector< double > parameters () const
 Retrieve parameters_.
virtual void parameters (const std::vector< double > &)
 Set parameters_ and send them to pInstance_.
virtual void mass (double m)
 Set mass used in unitLength().
void gmunu (double g[4][4], const double *x) const
int christoffel (double dst[4][4][4], const double *x) const
const std::string kind () const
 Get kind_.
int coordKind () const
 Get coordinate kind.
int getRefCount ()
 Get the current number of references.
void mass (const double, const std::string &unit)
 Set mass used in unitLength().
double mass () const
 Get mass used in unitLength().
double mass (const std::string &unit) const
 Get mass used in unitLength().
double unitLength () const
 M * G / c^2, M is in kg, unitLength in meters.
double unitLength (const std::string &unit) const
 unitLength expressed in specified unit
virtual double getRmb () const
virtual double getRms () const
virtual double getSpecificAngularMomentum (double rr) const
virtual double getPotential (double const pos[4], double l_cst) const
double deltaMin () const
void deltaMin (double h1)
double deltaMax () const
virtual double deltaMax (double const pos[8], double delta_max_external) const
void deltaMax (double h1)
double deltaMaxOverR () const
 Get delta_max_over_r_.
void deltaMaxOverR (double t)
 Set delta_max_over_r_.
bool keplerian () const
 Get keplerian_.
void keplerian (bool)
 Set keplerian_.
virtual void cartesianVelocity (double const coord[8], double vel[3])
 Compute xprime, yprime and zprime from 8-coordinates.
virtual double SysPrimeToTdot (const double coord[4], const double v[3]) const
 Compute tdot as a function of dr/dt, dtheta/dt and dphi/dt. Everything is in geometrical units.
virtual void circularVelocity (double const pos[4], double vel[4], double dir=1.) const
 Yield circular velocity at a given position.
virtual void nullifyCoord (double coord[8]) const
 Set tdot (coord[4]) such that coord is light-like. Everything is in geometrical units.
virtual void nullifyCoord (double coord[8], double &tdot2) const
 Set tdot (coord[4]) such that coord is light-like and return other possible tdot.
virtual double ScalarProd (const double pos[4], const double u1[4], const double u2[4]) const
 Scalar product.
virtual void observerTetrad (std::string const obskind, double const pos[4], double fourvel[4], double screen1[4], double screen2[4], double screen3[4]) const
 Computes the orthonormal local tetrad of the observer.
virtual double gmunu (double const x[4], int mu, int nu) const
 Metric coefficients.
virtual void gmunu (double g[4][4], double const pos[4]) const
 Metric coefficients.
virtual double christoffel (const double coord[4], const int alpha, const int mu, const int nu) const
 Chistoffel symbol.
virtual int christoffel (double dst[4][4][4], const double coord[4]) const
 Chistoffel symbol.
virtual int myrk4 (Worldline *line, const double coord[8], double h, double res[8]) const
 RK4 integrator.
virtual int myrk4_adaptive (Gyoto::Worldline *line, const double coord[8], double lastnorm, double normref, double coordnew[8], double h0, double &h1, double deltamax=GYOTO_DEFAULT_DELTA_MAX) const
 RK4 integrator with adaptive step.
virtual int isStopCondition (double const coord[8]) const
 Check whether integration should stop.
virtual int diff (const double y[8], double res[8]) const
 F function such as dy/dtau=F(y,cst).
virtual void setParticleProperties (Gyoto::Worldline *line, double const coord[8]) const
 Set Metric-specific constants of motion. Used e.g. in KerrBL.
void incRefCount ()
 Increment the reference counter. Warning: Don't mess with the counter.
int decRefCount ()
 Decrement the reference counter and return current value. Warning: Don't mess with the counter.
virtual bool isThreadSafe () const
 Whether this class is thread-safe.
void set (Property const &p, Value val)
 Set Value of a Property.
void set (Property const &p, Value val, std::string const &unit)
 Set Value (expressed in unit) of a Property.
void set (std::string const &pname, Value val)
 Set Value of a Property.
void set (std::string const &pname, Value val, std::string const &unit)
 Set Value (expressed in unit) of a Property.
Value get (Property const &p) const
 Get Value of a Property.
Value get (std::string const &pname) const
 Get Value of a Property.
Value get (Property const &p, std::string const &unit) const
 Get Value of a Property, converted to unit.
Value get (std::string const &pname, std::string const &unit) const
 Get Value of a Property, converted to unit.
Property const * property (std::string const pname) const
 Find property by name.
virtual void fillProperty (Gyoto::FactoryMessenger *fmp, Property const &p) const
 Output a single Property to XML.
virtual void fillElement (Gyoto::FactoryMessenger *fmp) const
 Fill the XML element for this Object.
virtual void setParameters (Gyoto::FactoryMessenger *fmp)
 Main loop for parsing Properties from XML description.
virtual int setParameter (std::string name, std::string content, std::string unit)
 Set parameter by name.
virtual void setParameter (Gyoto::Property const &p, std::string const &name, std::string const &content, std::string const &unit)
 Set parameter by Property (and name).
std::string describeProperty (Gyoto::Property const &p) const
 Format desrciption for a property.
void help () const
 Print (to stdout) some help on this class.
virtual void hook (Listener *listener)
 Start listening.
virtual void unhook (Listener *listener)
 Stop listening.

Public Attributes

 GYOTO_OBJECT_THREAD_SAFETY

Static Public Attributes

static GYOTO_OBJECT Property const properties []
 Property list.

Protected Member Functions

void kind (const std::string)
 Set kind_.
void coordKind (int coordkind)
 Set coordkind_.
virtual void tellListeners ()
 Call tell() on each hooked Listener.

Protected Attributes

double delta_min_
 Minimum integration step for the adaptive integrator.
double delta_max_
 Maximum integration step for the adaptive integrator.
double delta_max_over_r_
 Numerical tuning parameter.
bool keplerian_
 1 if circularVelocity should return the Newtonian Keplerian velocity, in r^-3/2
std::string kind_
 The "kind" that is output in the XML entity.
std::vector< std::string > plugins_
 The plug-ins that needs to be loaded to access this instance's class.
std::string module_
 Name of the Python module that holds the class.
std::string inline_module_
 Python source code for module that holds the class.
std::string class_
 Name of the Python class that we want to expose.
std::vector< double > parameters_
 Parameters that this class needs.
PyObject * pModule_
 Reference to the python module once it has been loaded.
PyObject * pInstance_
 Reference to the python instance once it has been instantiated.

Private Attributes

PyObject * pGmunu_
 Reference to the gmunu method.
PyObject * pChristoffel_
 Reference to the christoffel method.

Friends

class Gyoto::SmartPointer< Gyoto::Metric::Python >
class Gyoto::SmartPointer< Gyoto::Metric::Generic >
class Gyoto::Hook::Listener

Detailed Description

Metric coded in Python.

Loader for Python Metric classes. It interfaces with a Python class which must implement at least the methods detailed below.

Use <Cartesian> or </Spherical> to select the coordinate system kind.

Sample XML file:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<Scenery>

  The goal of this example is to exhibit using a Metric and a Spectrum
  coded in Python. It is functionaly equivalent to
  example-fixed-star-minkowski-cartesian.xml in the main Gyoto example
  directory.

  An optically thin blob centered on the origin of the coordinate
  system, in flat space-time. Computation uses the Cartesian
  coordinates.

  <Metric kind = "Python">
    <Mass unit="sunmass"> 4e6 </Mass>
    <Cartesian/>
    <Module>gyoto_sample_metrics</Module>
    <Class>Minkowski</Class>
  </Metric>

  <Screen>
    <Distance unit="kpc"> 8 </Distance>
    <Time unit="yr"> 30e3 </Time>
    <FieldOfView unit="microas"> 150 </FieldOfView>
    In UTF-8 locales, "microas" may be written "µas".
    <Inclination unit="degree"> 90 </Inclination>
    In UTF-8 locales, "degree" may be written "°".
    <PALN> 0 </PALN>
    <Argument> 0 </Argument>
    <Resolution> 32 </Resolution>
  </Screen>

  <Astrobj kind = "FixedStar">
    <Radius> 12 </Radius>
    <Position> 0 0 0 </Position>
    <UseGenericImpact/>
    <Spectrum kind="Python">
      <Module>gyoto_sample_spectra</Module>
      <Class>PowerLaw</Class>
      <Parameters>0.001 0.</Parameters>
    </Spectrum>
    <Opacity kind="Python">
      <Module>gyoto_sample_spectra</Module>
      <Class>PowerLaw</Class>
      <Parameters>0.001 0.</Parameters>
    </Opacity>
    <OpticallyThin/>
  </Astrobj>

  <Delta> 1e0 </Delta>
  <MinimumTime> 0. </MinimumTime>
  <Quantities>
    Intensity
  </Quantities>
  One can also specify a unit (if Gyoto was compiled with --with-udunits):
    Intensity[mJy/pix²]
    Intensity[mJy/µas²]
    Intensity[J.m-2.s-1.sr-1.Hz-1]
    Intensity[erg.cm-2.s-1.sr-1.Hz-1]
    Intensity[mJy.sr-1]
    Intensity[Jy.sr-1]

</Scenery>

Sample Python module:

'''Sample metrics for using with Gyoto Python plug-in

   Those classes demonstrate how to use Python classes as Gyoto
   Metric implementations using Gyoto's "python" plug-in. Note that
   this plug-in can be renamed to whatever matches the particular
   version of Python it has been built against (e.g. python3.4).

   The goal is to be able to instantiate these from XML, from
   Yorick... and even from Python using the gyoto extension...

   Synopsis:

   import gyoto.core
   gyoto.core.requirePlugin("python") # or python2.7 or python3.4...
   gg=gyoto.core.Metric("Python")
   gg.set("Module", "gyoto_sample_metric")
   gg.set("Class", "Minkowski")

   Classes that aim at implementing the Gyoto::Metric::Generic
   interface do so by providing the following methods:

   gmunu(self, dst, pos): mandatory;
   christoffel(self, dst, pos): mandatory
   __setattr__(self, key, value): optional
   __setitem__(self, key, value): optional

'''

import math
import numpy
import gyoto.core

class Minkowski:
    '''Flat space metric

    Implemented for both Cartesian and spherical coordinates.

    Every Gyoto Metric implemented in Python must implement the three
    methods illustrated here.

    '''
    def __setattr__(self, key, value):
        '''Set attributes.

        Optional.

        C++ will set several attributes. By overloading __setattr__,
        on can react when that occurs, in particular to make sure this
        knows the coordinate kind as in this example.

        Attributes set by the C++ layer:

          this: if the Python extension "gyoto.core" can be imported, it
                will be set to a gyoto.core.Metric instance pointing to the
                C++-side instance. If the "gyoto.core" extension cannot be
                loaded, this will be set to None.

          spherical: when the spherical(bool t) method is called in
                the C++ layer, it sets the spherical attribute in the
                Python side.

          mass: when the mass(double m) method is called in the C++
                side, it sets the spherical attribute in the Python
                side.

        This example initializes coordKind in the C++ side if it is
        not already set, since this Minkowski class can work in
        either.

        '''
        # First, actually store the attribute. This is what would
        # happen if we did not overload __setattr__.
        self.__dict__[key]=value
        # Then, if key is "this", ensure this knows a valid coordKind.
        if (key is "this"):
            cK=value.coordKind()
            if cK is gyoto.core.GYOTO_COORDKIND_UNSPECIFIED:
                value.set("Spherical", False)
            # We could do without this, since this will tell us later
            # anyway.
            else:
                self.spherical = (cK is gyoto.core.GYOTO_COORDKIND_SPHERICAL)

    def gmunu(self, g, x):
        ''' Gyoto::Metric::Generic::gmunu(double dst[4][4], const double pos[4])

        Mandatory.

        C++ will send two NumPy arrays.

        '''
        for mu in range(0, 4):
            for nu in range(0, 4):
                g[mu][nu]=g[nu][mu]=0
        g[0][0]=-1;
        if not self.spherical:
            for mu in range(1, 4):
                g[mu][mu]=1.
            return
        r=x[1]
        theta=x[2]
        tmp=r*math.sin(theta)
        g[1][1]=1.
        g[2][2]=r*r
        g[3][3]=tmp*tmp

    def christoffel(self, dst, x):
        '''Gyoto::Metric::Generic::christoffel(double dst[4][4][4], const double pos[4])

        Mandatory.

        C++ will send two NumPy arrays.

        '''
        for alpha in range(0, 4):
            for mu in range(0, 4):
                for nu in range(0, 4):
                    dst[alpha][mu][nu]=0.
        if not self.spherical:
            return 0
        r=x[1]
        theta=x[2]
        sth=math.sin(theta)
        cth=math.cos(theta)
        dst[1][2][2]=-r
        dst[1][3][3]=-r*sth*sth
        dst[2][1][2]=dst[2][2][1]= 1./r
        dst[2][3][3]=-sth*cth
        dst[3][1][3]=dst[3][3][1]= dst[2][1][2]
        dst[3][2][3]=dst[3][3][2]= math.tan(math.pi*0.5 - x[2])
        return 0

Member Typedef Documentation

typedef Gyoto::SmartPointer<Gyoto::SmartPointee> Gyoto::SmartPointee::Subcontractor_t(Gyoto::FactoryMessenger *, std::vector< std::string > const &) [inherited]

A subcontractor builds an object upon order from the Factory.

Various classes need to provide a subcontractor to be able to instantiate themselves upon order from the Factory. A subcontractor is a function (often a static member function) which accepts a pointer to a FactoryMessenger as unique parameter, communicates with the Factory using this messenger to read an XML description of the object to build, and returns this objet. SmartPointee::Subcontractor_t* is just generic enough a typedef to cast to and from other subcontractor types: Astrobj::Subcontractor_t, Metric::Subcontractor_t, Spectrum::Subcontractor_t. A subcontractor needs to be registered using the relevant Register() function: Astrobj::Register(), Metric::Register(), Spectrum::Register().


Member Function Documentation

virtual int Gyoto::Metric::Generic::christoffel ( double  dst[4][4][4],
const double  coord[4] 
) const [virtual, inherited]

Chistoffel symbol.

Value of Christoffel symbol at point (x1, x2, x3).

Returns:
1 on error, 0 otherwise

Reimplemented in Gyoto::Metric::KerrBL, Gyoto::Metric::KerrKS, Gyoto::Metric::Minkowski, and Gyoto::Metric::NumericalMetricLorene.

virtual double Gyoto::Metric::Generic::christoffel ( const double  coord[4],
const int  alpha,
const int  mu,
const int  nu 
) const [virtual, inherited]

Chistoffel symbol.

Value of Christoffel symbol at point (x1, x2, x3).

Reimplemented in Gyoto::Metric::Minkowski, and Gyoto::Metric::NumericalMetricLorene.

virtual void Gyoto::Metric::Generic::circularVelocity ( double const   pos[4],
double  vel[4],
double  dir = 1. 
) const [virtual, inherited]

Yield circular velocity at a given position.

Give the velocity of a massive particle in circular orbit at the given position projected onto the equatorial plane. Such a velocity may not exist everywhere (or anywhere) for a given metric. This method is intended to be used by Astrobj classes such as Torus or ThinDisk.

If keplerian_ is set to true, this method should return the Keplerian velcity instead (derived classes should ensure this, see KerrBL::circularVelocity() for instance).

The default implementation throws an error if keplerian_ is set to false.

Parameters:
pos input: position,
vel output: velocity,
dir 1 for corotating, -1 for counterrotating.

Reimplemented in Gyoto::Metric::ChernSimons, Gyoto::Metric::KerrBL, Gyoto::Metric::KerrKS, and Gyoto::Metric::RezzollaZhidenko.

void Gyoto::Metric::Generic::coordKind ( int  coordkind  )  [protected, inherited]

Set coordkind_.

coordkind(int coordkind) is protected because, for most Metrics, it should not be changed in runtime. Set coordinate kind

void Gyoto::Metric::Generic::deltaMax ( double  h1  )  [inherited]

Set delta_max_

virtual double Gyoto::Metric::Generic::deltaMax ( double const   pos[8],
double  delta_max_external 
) const [virtual, inherited]

Get delta max at a given position

Parameters:
pos 4-position
optional] delta_max_external external constraint on delta_max
Returns:
the smallest value between delta_max_, delta_max_external, and R*delta_max_over_r_ where R is pos[1] in spherical coordinates and max(x1, x2, x3) in Cartesian coordinates.
double Gyoto::Metric::Generic::deltaMax (  )  const [inherited]

Get delta_max_

void Gyoto::Metric::Generic::deltaMin ( double  h1  )  [inherited]

Set delta_min_

double Gyoto::Metric::Generic::deltaMin (  )  const [inherited]

Get delta_min_

std::string Gyoto::Object::describeProperty ( Gyoto::Property const &  p  )  const [inherited]

Format desrciption for a property.

Returns a string containing the name(s) and type of the property, as well as whether it supports unit.

virtual void Gyoto::Object::fillElement ( Gyoto::FactoryMessenger fmp  )  const [virtual, inherited]

Fill the XML element for this Object.

The base implementation simply calls fillProperty() for each Property defined for the Object.

Derived classes should avoid overriding fillElement(). It may make sense occasionally, e.g. to make sure that the metric is output first.

To customize how a given Property is rendered, it is better to override fillProperty().

If this method is overridden, the implementation should in general call fillElement() on the direct base.

Reimplemented in Gyoto::Astrobj::Complex, Gyoto::Spectrometer::Complex, and Gyoto::Scenery.

virtual void Gyoto::Object::fillProperty ( Gyoto::FactoryMessenger fmp,
Property const &  p 
) const [virtual, inherited]

Output a single Property to XML.

The base implementation decides what to do based on the p.type. The format matches how setParameters() an setParameter() would interpret the XML descition.

Overriding this method should be avoided, but makes sense in some cases (for instance Screen::fillProperty() selects a different unit for Distance based on its magnitude, so that stellar sizes are expressed in solar radii while smaller sizes can be expressed in meters and larger sizes in parsecs).

Overriding implementation should fall-back on calling the implementation in the direct parent class:

 class A: public Object {};
 class B: public A { 
  using B::setParameter;
  virtual void fillProperty(Gyoto::FactoryMessenger *fmp,
                        Property const &p) const ;
 };
 void B::fillProperty(Gyoto::FactoryMessenger *fmp,
                        Property const &p) const {
   if (name=="Duff") fmp->doSomething();
   else A::fillProperty(fmp, p);
 }

Reimplemented in Gyoto::Astrobj::DirectionalDisk, Gyoto::Astrobj::Disk3D, Gyoto::Astrobj::EquatorialHotSpot, Gyoto::Astrobj::NeutronStarModelAtmosphere, Gyoto::Astrobj::PatternDisk, Gyoto::Astrobj::PolishDoughnut, Gyoto::Scenery, Gyoto::Screen, Gyoto::Astrobj::Star, and Gyoto::Spectrometer::Uniform.

virtual double Gyoto::Metric::Generic::getPotential ( double const   pos[4],
double  l_cst 
) const [virtual, inherited]

Returns potential W=-ln(|u_t|) for a cst specific angular momentum l_cst Should be implemented in derived classes if useful If called on the base class, returns an error

Reimplemented in Gyoto::Metric::KerrBL, Gyoto::Metric::NumericalMetricLorene, and Gyoto::Metric::RezzollaZhidenko.

virtual Property const* Gyoto::Metric::Python::getProperties (  )  const [virtual]

Get list of properties.

This method is declared automatically by the GYOTO_OBJECT macro and defined automatically by the GYOTO_PROPERTY_END macro.

Reimplemented from Gyoto::Metric::Generic.

virtual double Gyoto::Metric::Generic::getRmb (  )  const [virtual, inherited]

Returns the marginally bound radius Should be implemented in derived classes if useful If called on the base class, returns an error

Reimplemented in Gyoto::Metric::KerrBL, Gyoto::Metric::NumericalMetricLorene, and Gyoto::Metric::RezzollaZhidenko.

virtual double Gyoto::Metric::Generic::getRms (  )  const [virtual, inherited]

Returns the marginally stable (ISCO) radius Should be implemented in derived classes if useful If called on the base class, returns an error

Reimplemented in Gyoto::Metric::KerrBL, Gyoto::Metric::NumericalMetricLorene, and Gyoto::Metric::RezzollaZhidenko.

virtual double Gyoto::Metric::Generic::getSpecificAngularMomentum ( double  rr  )  const [virtual, inherited]

Returns the specific angular momentum l=-u_phi/u_t Should be implemented in derived classes if useful If called on the base class, returns an error

Reimplemented in Gyoto::Metric::KerrBL, Gyoto::Metric::NumericalMetricLorene, and Gyoto::Metric::RezzollaZhidenko.

virtual void Gyoto::Metric::Generic::gmunu ( double  g[4][4],
double const   pos[4] 
) const [virtual, inherited]

Metric coefficients.

The default implementation calls double gmunu(const double * x, int mu, int nu) const.

Parameters:
[out] g 4x4 array to store the coeefficients
[in] x 4-position at which to compute the coefficients;
Returns:
Metric coefficient g, at point x

Reimplemented in Gyoto::Metric::KerrKS, and Gyoto::Metric::Minkowski.

virtual double Gyoto::Metric::Generic::gmunu ( double const   x[4],
int  mu,
int  nu 
) const [virtual, inherited]

Metric coefficients.

The default implementation calls Metric:: gmunu(double g[4][4], const double * pos) const

Parameters:
x 4-position at which to compute the coefficient;
mu 1st index of coefficient, 03;
nu 2nd index of coefficient, 03;
Returns:
Metric coefficient g, at point x

Reimplemented in Gyoto::Metric::KerrKS, Gyoto::Metric::Minkowski, and Gyoto::Metric::NumericalMetricLorene.

void Gyoto::Object::help (  )  const [inherited]

Print (to stdout) some help on this class.

Describe all properties that this instance supports.

virtual void Gyoto::Hook::Teller::hook ( Listener listener  )  [virtual, inherited]

Start listening.

Use from a Hook::Listener object method:

 teller->hook(this)

where "this" is a Listener and "teller" is a Teller.

Use unhook() later to stop listening to a given Teller.

Parameters:
listener pointer to the new listener
virtual void Gyoto::Metric::Python::inlineModule ( const std::string &   )  [virtual]

Set inline_module_ and import the Python module.

Side effects:

Reimplemented from Gyoto::Python::Base.

virtual int Gyoto::Metric::Generic::isStopCondition ( double const   coord[8]  )  const [virtual, inherited]

Check whether integration should stop.

The integrating loop will ask this the Metric through this method whether or not it is happy to continue the integration. Typically, the Metric should answer 0 when everything is fine, 1 when too close to the event horizon, inside the BH...

Parameters:
coord 8-coordinate vector to check.
virtual bool Gyoto::Object::isThreadSafe (  )  const [virtual, inherited]

Whether this class is thread-safe.

Return True if this object is thread-safe, i.e. if an instance and its clone can be used in parallel threads (in the context of Scenery::raytrace()). Known objects which are not thread-safe include Lorene metrics and everything from the Python plug-in.

The default implementation considers that the class itself is thread safe and recurses into the declared properties to check whether they are safe too. Classes that abide to the Object/Property paradigm and are themselves thread-safe have nothing special to do.

Objects that clone children in their copy constructor that are not declared as properties must take these children into account.

Classes that are never thread-safe must declare it. It acn be easily done using GYOTO_OBJECT_THREAD_SAFETY in the class declaration and GYOTO_PROPERTY_THREAD_UNSAFE in the class definition.

void Gyoto::Metric::Generic::kind ( const std::string   )  [protected, inherited]

Set kind_.

kind(const std::string) is protected because, for most Metrics, it should not be changed in runtime. Set kind_

virtual void Gyoto::Metric::Python::klass ( const std::string &  c  )  [virtual]

Set class_ and instantiate the Python class.

Sets pInstance_.

This generic implementation takes care of the common ground, but does not set 'this' or call parameters(parameters_). Therefore, all the derived classes should reimplement this method and at least call Python::Base::klass(c) and parameters(parameters_). Between the two is the right moment to check that the Python class implements the required API and to cache PyObject* pointers to class methods.

Reimplemented from Gyoto::Python::Base.

virtual void Gyoto::Metric::Python::module ( const std::string &   )  [virtual]

Set module_ and import the Python module.

Side effects:

Reimplemented from Gyoto::Python::Base.

virtual void Gyoto::Metric::Generic::nullifyCoord ( double  coord[8],
double &  tdot2 
) const [virtual, inherited]

Set tdot (coord[4]) such that coord is light-like and return other possible tdot.

Set coord[4] so that the 4-velocity coord[4:7] is lightlike, i.e. of norm 0. There may be up to two solutions. coord[4] is set to the hightest. The lowest can be retrieved in tdot2. Everything is expressed in geometrical units.

Parameters:
[in,out] coord 8-position, coord[4] will be set according to the other elements;
[out] tdot2 will be set to the smallest solution

Reimplemented in Gyoto::Metric::KerrBL.

virtual void Gyoto::Metric::Generic::nullifyCoord ( double  coord[8]  )  const [virtual, inherited]

Set tdot (coord[4]) such that coord is light-like. Everything is in geometrical units.

Set coord[4] so that the 4-velocity coord[4:7] is lightlike, i.e. of norm 0. There may be up to two solutions. coord[4] is set to the hightest. The lowest can be retrieved using nullifyCoord(double coord[8], double& tdot2) const. Everything is expressed in geometrical units.

Parameters:
[in,out] coord 8-position, coord[4] will be set according to the other elements;

Reimplemented in Gyoto::Metric::KerrBL.

virtual void Gyoto::Metric::Generic::observerTetrad ( std::string const   obskind,
double const   pos[4],
double  fourvel[4],
double  screen1[4],
double  screen2[4],
double  screen3[4] 
) const [virtual, inherited]

Computes the orthonormal local tetrad of the observer.

Parameters:
obskind input: kind of observer (eg: "ZAMO","KeplerianObserver"...)
pos input: position,
fourvel output: observer 4-velocity (norm -1)
screen1 output: first vector in the screen plane
screen2 output: second vector in the screen plane
screen3 output: vector normal to the screen

Reimplemented in Gyoto::Metric::KerrBL, and Gyoto::Metric::Minkowski.

virtual void Gyoto::Metric::Python::parameters ( const std::vector< double > &   )  [virtual]

Set parameters_ and send them to pInstance_.

The parameters are sent to the class instance using the __setitem__ method with numerical keys.

Reimplemented from Gyoto::Python::Base.

Property const* Gyoto::Object::property ( std::string const   pname  )  const [inherited]

Find property by name.

Look into the Property list for a Property whose name (or name_false, for a boolean Property) is pname. Return a const pointer to the first such property found, or NULL if none is found.

virtual double Gyoto::Metric::Generic::ScalarProd ( const double  pos[4],
const double  u1[4],
const double  u2[4] 
) const [virtual, inherited]

Scalar product.

Compute the scalarproduct of the two quadrivectors u1 and u2 in this Metric, at point pos expressed in coordinate system sys.

Parameters:
pos 4-position;
u1 1st quadrivector;
u2 2nd quadrivector;
Returns:
u1*u2

Reimplemented in Gyoto::Metric::KerrBL, and Gyoto::Metric::RotStar3_1.

virtual void Gyoto::Object::setParameter ( Gyoto::Property const &  p,
std::string const &  name,
std::string const &  content,
std::string const &  unit 
) [virtual, inherited]

Set parameter by Property (and name).

This function is used when parsing an XML description, if Property (p) of this name is found (i.e. either p.name or p.name_false is equal to name). Implementation should fall-back on calling the direct's parent implementation:

 class A: public Object {};
 class B: public A { 
  using B::setParameter;
  virtual void setParameter(Gyoto::Property const &p,
                            std::string name,
                                std::string content,
                                std::string unit);
 };
 void B::setParameter(Gyoto::Property const &p,
                          std::string name,
                          std::string content,
                          std::string unit) {
   if (name=="Duff") doSomething(content, unit);
   else A::setParameter(p, name, content, unit);
 }
Parameters:
p Property that matches name (p.name == name or p.name_false == name)
name XML name of the parameter (XML entity)
content string representation of the value
unit string representation of the unit

Reimplemented in Gyoto::Astrobj::PolishDoughnut.

virtual int Gyoto::Object::setParameter ( std::string  name,
std::string  content,
std::string  unit 
) [virtual, inherited]

Set parameter by name.

This function is used when parsing an XML description, if no Property of this name is found. Overriding implementation should fall-back on calling the direct's parent implementation:

 class A: public Object {};
 class B: public A { 
  using B::setParameter;
  virtual int setParameter(std::string name,
                            std::string content,
                            std::string unit);
 };
 int B::setParameter(std::string name,
                            std::string content,
                            std::string unit) {
   if (name=="Duff") doSomething(content, unit);
   else return A::setParameter(name, content, unit);
   return 0;  // name was known
 }
Parameters:
name XML name of the parameter (XML entity). This may have a path component, e.g. "Astrobj::Radius", in which case a property named "Astrobj" will be sought in the current object, and setParameter will be called recusrively on this Astrobj with Radius as name.
content string representation of the value
unit string representation of the unit
Returns:
0 if this parameter is known, 1 if it is not.

Reimplemented in Gyoto::Astrobj::EquatorialHotSpot, Gyoto::Metric::KerrKS, Gyoto::Metric::RotStar3_1, and Gyoto::Astrobj::Star.

virtual void Gyoto::Object::setParameters ( Gyoto::FactoryMessenger fmp  )  [virtual, inherited]

Main loop for parsing Properties from XML description.

This function queries the FactoryMessenger for elements to parse, and tries to matche each element to a Property to set it accordingly.

Any class that tries to be buildable from XML must supply a subcontractor (for base classes such as Metric, Astrobj, Spectrum and Spectrometer, it is done as a template that must be specialized for each class).

This subcontractor typically looks somewhat like this:

SmartPointer<Metric::Generic>
Gyoto::Metric::MyKind::Subcontractor(FactoryMessenger* fmp) {
  SmartPointer<MyKind> gg = new MyKind();
  gg -> setParameters(fmp);
  return gg;
}

Although this is discouraged, it is possible to override the following functions to customize how XML entities are parsed:

  • setParameters() if low-level access to the FactoryMessenger is required;
  • setParameter(std::string name, std::string content, std::string unit) to interpret an entity that does not match a Property (e.g. alternative name);
  • setParameter(Gyoto::Property const &p, std::string const &name, std::string const &content, std::string const &unit) to change how a Property is interpreted.

Reimplemented in Gyoto::Astrobj::Generic, Gyoto::Astrobj::Complex, Gyoto::Spectrometer::Complex, Gyoto::Astrobj::EquatorialHotSpot, Gyoto::Astrobj::OscilTorus, Gyoto::Photon, Gyoto::Astrobj::Star, and Gyoto::Spectrometer::Uniform.

virtual double Gyoto::Metric::Generic::SysPrimeToTdot ( const double  coord[4],
const double  v[3] 
) const [virtual, inherited]

Compute tdot as a function of dr/dt, dtheta/dt and dphi/dt. Everything is in geometrical units.

Parameters:
coord 4-position (geometrical units);
v 3-velocity dx1/dx0, dx2/dx0, dx3/dx0;
Returns:
tdot = dx0/dtau.
virtual void Gyoto::Hook::Teller::tellListeners (  )  [protected, virtual, inherited]

Call tell() on each hooked Listener.

Whenever a Teller mutates, it should warn any Listener hooked to it using tellListeners().

virtual void Gyoto::Hook::Teller::unhook ( Listener listener  )  [virtual, inherited]

Stop listening.

Use from a Hook::Listener object method:

 teller->unhook(this)

where "this" is a Listener, "teller" is a Teller, and "this" has called teller->hook(this) previously.

Parameters:
listener pointer to the listener
double Gyoto::Metric::Generic::unitLength (  )  const [inherited]

M * G / c^2, M is in kg, unitLength in meters.

Metrics implementations are free to express lengths and distances in whatever unit they see fit (presumably most often geometrical units). This function returns this unit in SI (meters).


Member Data Documentation

std::string Gyoto::Python::Base::class_ [protected, inherited]

Name of the Python class that we want to expose.

Property name: Class.

double Gyoto::Metric::Generic::delta_max_over_r_ [protected, inherited]

Numerical tuning parameter.

Ensure that delta (the numerical integration step) is never larger than a fraction of the distance between the current location and the center of the coordinate system.

For investigations close to the event horizon, 0.5 is usually fine. If high accuracy is needed long after deflection (weak lensing), then this must be smaller. A good test is to look at a MinDistance map for a FixedStar: it must be smooth.

std::string Gyoto::Object::kind_ [protected, inherited]

The "kind" that is output in the XML entity.

E.g. for an Astrobj, fillElement() will ensure

   <Astrobj kind="kind_" ...>...</Astrobj>

is written.

std::string Gyoto::Python::Base::module_ [protected, inherited]

Name of the Python module that holds the class.

For instance, if the class is implemented in toto.py, the module name is "toto". Property name: Module.

std::vector<double> Gyoto::Python::Base::parameters_ [protected, inherited]

Parameters that this class needs.

A list of parameters (doubles) can be passed in the Property Parameters. They will be sent to the Python instance using __setitem__.

std::vector<std::string> Gyoto::Object::plugins_ [protected, inherited]

The plug-ins that needs to be loaded to access this instance's class.

E.g. for an Astrobj, fillElement() will ensure

   <Astrobj ... plugin="plugins_">...</Astrobj>

is written.

GYOTO_OBJECT Property const Gyoto::Metric::Python::properties[] [static]

Property list.

This static member is declared automatically by the GYOTO_OBJECT macro and defined automatically by the GYOTO_PROPERTY_START, GYOTO_PROPERTY_END and GYOTO_PROPERTY_* macros.

The list of properties is implemented as a static array of Property instances. The last item in a Property of type Property::empty_t, which evaluates to false, so the list can be considered to be NULL-terminated (it is actually rather false-terminated). This empty_t last item can be a link to another Property list: for instance, the last item in Gyoto::Astrobj::Standard::properties is a link to Gyoto::Astrobj::Generic::properties.

Reimplemented from Gyoto::Metric::Generic.


The documentation for this class was generated from the following file:

Generated on 6 May 2017 for Gyoto by  doxygen 1.6.1