model_polarized_image_sum Class Reference
Defines a summed polarized image model. More...
#include "model/model_polarized_image_sum.h"
Inheritance diagram for model_polarized_image_sum:
Collaboration diagram for model_polarized_image_sum:
Public Member Functions | |
| model_polarized_image_sum (std::vector< model_polarized_image * > images, std::string offset_coordinates="Cartesian") | |
| Constructor. Takes a vector of pointers to model_polarized_image objects. | |
| model_polarized_image_sum (std::string offset_coordinates="Cartesian") | |
| Constructor. Makes empty sum object, models can be added with add_model_polarized_image. | |
| virtual | ~model_polarized_image_sum () |
| Constructor. Takes a pair of model_polarized_image objects. | |
| void | add_model_polarized_image (model_polarized_image &image) |
| Add an image. | |
| virtual void | generate_model (std::vector< double > parameters) |
| A user-supplied function that returns the number of the parameters the model expects. More... | |
| virtual std::vector< std::complex< double > > | crosshand_visibilities (datum_crosshand_visibilities &d, double accuracy) |
| Returns a vector of complex visibility corresponding to RR,LL,RL,LR in Jy computed from the image given a datum_crosshand_visibilities_amplitude object, containing all of the accoutrements. While this provides access to the actual data value, the two could be separated if necessary. Also takes an accuracy parameter with the same units as the data, indicating the accuracy with which the model must generate a comparison value. Note that this can be redefined in child classes. | |
| virtual std::complex< double > | visibility (datum_visibility &d, double acc) |
| Returns complex visibility in Jy computed from the image given a datum_visibility_amplitude object, containing all of the accoutrements. While this provides access to the actual data value, the two could be separated if necessary. Also takes an accuracy parameter with the same units as the data, indicating the accuracy with which the model must generate a comparison value. Note that this is redefined to accomodate the possibility of using the analytical computation. | |
| virtual double | visibility_amplitude (datum_visibility_amplitude &d, double acc) |
| Returns visibility ampitudes in Jy computed from the image given a datum_visibility_amplitude object, containing all of the accoutrements. While this provides access to the actual data value, the two could be separated if necessary. Also takes an accuracy parameter with the same units as the data, indicating the accuracy with which the model must generate a comparison value. Note that this is redefined to accomodate the possibility of using the analytical computation. | |
| virtual double | closure_phase (datum_closure_phase &d, double acc) |
| Returns closure phase in degrees computed from the image given a datum_closure_phase object, containing all of the accoutrements. While this provides access to the actual data value, the two could be separated if necessary. Also takes an accuracy parameter with the same units as the data, indicating the accuracy with which the model must generate a comparison value. Note that this is redefined since the closure phase of Gaussian images is identically zero. | |
| virtual double | closure_amplitude (datum_closure_amplitude &d, double acc) |
| Returns closure amplitude computed from the image given a datum_closure_phase object, containing all of the accoutrements. While this provides access to the actual data value, the two could be separated if necessary. Also takes an accuracy parameter with the same units as the data, indicating the accuracy with which the model must generate a comparison value. Note that this can be redefined in child classes. | |
| virtual std::string | model_tag () const |
| A user-supplied function that returns the closure amplitudes. Takes a datum_polarization_fraction to provide access to the various accoutrements. While this provides access to the actual data value, the two could be separated if necessary. Also takes an accuracy parameter with the same units as the data, indicating the accuracy with which the model must generate a comparison value. More... | |
 Public Member Functions inherited from model_polarized_image | |
| virtual size_t | size () const |
| A user-supplied function that returns the number of the parameters the model expects. | |
| void | model_Dterms (std::vector< std::string > station_codes) |
| Add D-terms, increases the number of parameters by four times the number of station codes passed. Will fail if a visibility is requested for a station for which the code has not been provided. | |
| bool | modeling_Dterms () const |
| Boolean to determine if this is fitting D-terms. | |
| size_t | number_of_Dterms () const |
| Number of D-terms (each complex number) | |
| virtual void | generate_complex_visibilities () |
| A one-time generate function that will generate the complex visibilities and store them. This must be called after generate_model has been called. | |
| virtual double | polarization_fraction (datum_polarization_fraction &d, double accuracy) |
| A user-supplied function that returns the closure amplitudes. Takes a datum_polarization_fraction to provide access to the various accoutrements. While this provides access to the actual data value, the two could be separated if necessary. Also takes an accuracy parameter with the same units as the data, indicating the accuracy with which the model must generate a comparison value. | |
| void | output_image (std::string fname, bool rotate=false) |
| void | get_image (std::vector< std::vector< double > > &alpha, std::vector< std::vector< double > > &beta, std::vector< std::vector< double > > &I) const |
| Provides direct access to the constructed image. Sets a 2D grid of angles (alpha, beta) in radians and intensities in Jy per steradian. | |
| void | get_image (std::vector< std::vector< double > > &alpha, std::vector< std::vector< double > > &beta, std::vector< std::vector< double > > &I, std::vector< std::vector< double > > &Q, std::vector< std::vector< double > > &U, std::vector< std::vector< double > > &V) const |
| Provides direct access to the constructed image in all Stokes parameters. Sets a 2D grid of angles (alpha, beta) in radians and intensities in Jy per steradian. | |
| void | get_visibilities (std::vector< std::vector< double > > &u, std::vector< std::vector< double > > &v, std::vector< std::vector< std::complex< double > > > &VI) const |
| Provides direct access to the complex visibilities. Sets a 2D grid of baselines (u,v) in lambda, and visibilites in Jy. | |
| void | get_visibilities (std::vector< std::vector< double > > &u, std::vector< std::vector< double > > &v, std::vector< std::vector< std::complex< double > > > &RR, std::vector< std::vector< std::complex< double > > > &LL, std::vector< std::vector< std::complex< double > > > &RL, std::vector< std::vector< std::complex< double > > > &LR) const |
| Provides direct access to the crosshand complex visibilities. Sets a 2D grid of baselines (u,v) in lambda, and visibilites in Jy. | |
| void | get_visibility_amplitudes (std::vector< std::vector< double > > &u, std::vector< std::vector< double > > &v, std::vector< std::vector< double > > &V) const |
| Provides direct access to the visibility amplitudes. Sets a 2D grid of baselines (u,v) in lambda, and visibilites in Jy. | |
| void | use_spline_interp (bool use_spline) |
| Provides ability to use bicubic spline interpolator (true) instead of regular bicubic. Code defaults to false. | |
| virtual void | set_mpi_communicator (MPI_Comm comm) |
| Defines a set of processors provided to the model for parallel computation via an MPI communicator. Only facilates code parallelization if the model computation is parallelized via MPI. | |
| void | write_model_tag_file (std::string tagfilename="model_image.tag") const |
| Write a unique identifying tag for use with the ThemisPy plotting features. This calls the overloaded version with the outstream, which is the only function that need be rewritten in child classes. | |
| virtual void | write_model_tag_file (std::ofstream &tagout) const |
| Write a unique identifying tag for use with the ThemisPy plotting features. For most child classes, the default implementation is suffcient. However, should that not be the case, this is the only function that need be rewritten in child classes. | |
Private Member Functions | |
| virtual void | generate_polarized_image (std::vector< double > parameters, std::vector< std::vector< double > > &I, std::vector< std::vector< double > > &Q, std::vector< std::vector< double > > &U, std::vector< std::vector< double > > &V, std::vector< std::vector< double > > &alpha, std::vector< std::vector< double > > &beta) |
| Note that this is not defined because there is no uniform image size/resolution specification. | |
| virtual void | generate_image (std::vector< double > parameters, std::vector< std::vector< double > > &I, std::vector< std::vector< double > > &alpha, std::vector< std::vector< double > > &beta) |
| Note that this is not defined because there is no uniform image size/resolution specification. | |
Private Attributes | |
| std::vector< model_polarized_image * > | _images |
| std::string | _offset_coordinates |
| Choose coordinate system in which to specify offset ("Cartesian","polar") | |
| std::vector< double > | _x |
| x offset position in radians | |
| std::vector< double > | _y |
| y offset position in radians | |
Additional Inherited Members | |
| Protected Member Functions inherited from model_polarized_image | |
| void | apply_Dterms (const datum_crosshand_visibilities &d, std::vector< std::complex< double > > &crosshand_vector) const |
| Applies the D-terms. Checks if modeling inside and must be called in crosshand_visibilities if redefined by child classes. | |
| void | read_and_strip_Dterm_parameters (std::vector< double > ¶meters) |
| Reads and remove Dterm parameters from the parameter list. Checks if modeling inside and must be called in crosshand_visibilities if redefined by child classes. | |
| Protected Attributes inherited from model_polarized_image | |
| MPI_Comm | _comm |
| bool | _generated_model |
| True when a model is generated with generate_model. | |
| bool | _generated_visibilities |
| True when model visibilities have been computed. | |
| bool | _use_spline |
| True when want to use bicubic spline interpolator. | |
| double | _position_angle |
| Position angle of the image, assumed to be the last element of the parameter list passed to generate_model. Assumed to be in radians and defined E of N. | |
| std::vector< double > | _current_parameters |
| Last set of parameters passed to generate_image, useful to determine if it is necessary to recompute the model. Useful, e.g., if we are varying only position angle, or if recomputing for a number of different data sets at the same set of parameters. | |
| std::vector< std::vector< double > > | _alpha |
| 2D grid of horizonal pixel locations in radians, relative to the fiducial direction of the image (i.e., unrotated by the position angle). | |
| std::vector< std::vector< double > > | _beta |
| 2D grid of vertical pixel locations in radians, relative to the fiducial direction of the image (i.e., unrotated by the position angle). | |
| std::vector< std::vector< double > > | _I |
| std::vector< std::vector< double > > | _Q |
| std::vector< std::vector< double > > | _U |
| std::vector< std::vector< double > > | _V |
| 2D grid of intensities at pixel locations in Jy/str. | |
| size_t | _size |
| bool | _modeling_Dterms |
| std::vector< std::string > | _station_codes |
| Protected Attributes inherited from model_crosshand_visibilities | |
| MPI_Comm | _comm |
| Protected Attributes inherited from model_polarization_fraction | |
| MPI_Comm | _comm |
| Protected Attributes inherited from model_visibility | |
| MPI_Comm | _comm |
| Protected Attributes inherited from model_visibility_amplitude | |
| MPI_Comm | _comm |
| Protected Attributes inherited from model_closure_phase | |
| MPI_Comm | _comm |
| Protected Attributes inherited from model_closure_amplitude | |
| MPI_Comm | _comm |
Detailed Description
Each polarized image component has its full complement of parameters, appended in order of the summation. The resulting image is simply the sum of the intensity map from the each underlying object. This sum is performed in the visibilty plane.
Parameter list:
- parameters[0] ... Model 1 parameters[0].
...
- parameters[N1-1] ... Model 1 last parameter.
- parameters[N1] ... Model 1 offset in x.
- parameters[N1+1] ... Model 1 offset in y.
- parameters[N1+2] ... Model 2 parameters[0].
...
- parameters[N1+N2+1] ... Model 2 last parameter.
- parameters[N1+N2+2] ... Model 2 offset in x.
- parameters[N1+N2+3] ... Model 2 offset in y.
...
- parameters[-1] ... Position angle (in model_polarized_image) in radians
Note that offsets for all components are included. These are often not necessary, and can be set to fixed values via priors if needed.
- Todo:
- Implement polarization fraction.
Member Function Documentation
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virtual |
A one-time generate function that permits model construction prior to calling the visibility_amplitude, closure_phase, etc. for each datum. Takes a vector of parameters.
Reimplemented from model_polarized_image.
Here is the call graph for this function:
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virtual |
Return a string that contains a unique identifying tag for use with the ThemisPy plotting features. This function SHOULD be defined in subsequent model_image classes with a unique identifier that contains sufficient information about the hyperparameters to uniquely determine the image. By default it writes "UNDEFINED"
Reimplemented from model_polarized_image.
The documentation for this class was generated from the following files: