ObitTimeFilter.h File Reference

ObitTimeFilter time filter class definition. More...

#include "ObitThread.h"
#include "ObitFArray.h"
#include "ObitCArray.h"
#include "ObitFFT.h"
#include "ObitFInterpolate.h"

Go to the source code of this file.

Classes
struct	ObitTimeFilter
	ObitTimeFilter Class structure. More...
struct	ObitTimeFilterClassInfo
	ClassInfo Structure. More...
Defines
#define	ObitTimeFilterUnref(in)   ObitUnref (in)
	Macro to unreference (and possibly destroy) an ObitTimeFilter returns a ObitTimeFilter*.
#define	ObitTimeFilterRef(in)   ObitRef (in)
	Macro to reference (update reference count) an ObitTimeFilter.
#define	ObitTimeFilterIsA(in)   ObitIsA (in, ObitTimeFilterGetClass())
	Macro to determine if an object is the member of this or a derived class.
Typedefs
typedef ObitTimeFilter *(*	newObitTimeFilterFP )(gchar *name, gint nTime, gint nFilter)
	Typedef for definition of class pointer structure.
typedef void(*	ObitTimeFilter2FreqFP )(ObitTimeFilter *in)
typedef void(*	ObitTimeFilter2TimeFP )(ObitTimeFilter *in)
typedef void(*	ObitTimeFilterFilterFP )(ObitTimeFilter *in, gint seriesNo, ObitTimeFilterType type, gfloat *parms, ObitErr *err)
Enumerations
enum	obitTimeFilterType { OBIT_TimeFilter_LowPass, OBIT_TimeFilter_HighPass }
	enum for type of ObitTimeFilter filter type. More...
Functions
void	ObitTimeFilterClassInit (void)
	Public: Class initializer.
ObitTimeFilter *	newObitTimeFilter (gchar *name, gint nTime, gint nSeries)
	Public: Constructor.
gconstpointer	ObitTimeFilterGetClass (void)
	Public: ClassInfo pointer.
void	ObitTimeFilterResize (ObitTimeFilter *in, gint nTime)
	Public: Resize arrays.
void	ObitTimeFilter2Freq (ObitTimeFilter *in)
	Public: Compute frequency series.
void	ObitTimeFilter2Time (ObitTimeFilter *in)
	Public: Compute Time series.
void	ObitTimeFilterFilter (ObitTimeFilter *in, gint seriesNo, ObitTimeFilterType type, gfloat *parms, ObitErr *err)
	Public: Apply Filter to Frequency series.

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Detailed Description

ObitTimeFilter time filter class definition.

This class is derived from the Obit class.

This class is for performing TimeFilter on memory resident data. This implem,entation uses the TimeFilterW package.

Creators and Destructors

An ObitTimeFilter can be created using newObitTimeFilter which allows specifying a name for the object, and the type, size and direction of the transform.

A copy of a pointer to an ObitTimeFilter should always be made using the ObitTimeFilterRef function which updates the reference count in the object. Then whenever freeing an ObitTimeFilter or changing a pointer, the function ObitTimeFilterUnref will decrement the reference count and destroy the object when the reference count hits 0. There is no explicit destructor.

Creators and Destructors

An ObitTimeFilter provides storage for one or more time series of floats in both the time and frequency (half complex) domains. The class also contains tools for transforming from one domain to the other and for applying a filter in the frequency domain. Typcal usage sequence is:

• Create using newObitTimeFilter
• fill time series data using #timeData gfloat pointer member
• transform to frequency using ObitTimeFilter2Freq
• apply filter using ObitTimeFilterFilter
• transform back to time domain using ObitTimeFilter2Time
• access filter time series using #timeData gfloat pointer member
• unreference object using ObitTimeFilterUnref

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Define Documentation

#define ObitTimeFilterIsA (  in   )     ObitIsA (in, ObitTimeFilterGetClass())

Macro to determine if an object is the member of this or a derived class. Returns TRUE if a member, else FALSE in = object to reference

#define ObitTimeFilterRef (  in   )     ObitRef (in)

Macro to reference (update reference count) an ObitTimeFilter. returns a ObitTimeFilter*. in = object to reference

#define ObitTimeFilterUnref (  in   )     ObitUnref (in)

Macro to unreference (and possibly destroy) an ObitTimeFilter returns a ObitTimeFilter*. in = object to unreference

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Typedef Documentation

typedef ObitTimeFilter*(* newObitTimeFilterFP)(gchar *name, gint nTime, gint nFilter)

Typedef for definition of class pointer structure.

typedef void(* ObitTimeFilter2FreqFP)(ObitTimeFilter *in)

typedef void(* ObitTimeFilter2TimeFP)(ObitTimeFilter *in)

typedef void(* ObitTimeFilterFilterFP)(ObitTimeFilter *in, gint seriesNo, ObitTimeFilterType type, gfloat *parms, ObitErr *err)

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Enumeration Type Documentation

enum obitTimeFilterType

enum for type of ObitTimeFilter filter type. This specifies the type of filtering to be performed. Enumeration values: OBIT_TimeFilter_LowPass  Low pass filter. OBIT_TimeFilter_HighPass  High pass filter.

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Function Documentation

ObitTimeFilter* newObitTimeFilter (  gchar *  name, gint  nTime, gint  nSeries )

Public: Constructor. Initializes class if needed on first call. Parameters: name  An optional name for the object. nTime  Number of times in arrays to be filtered It is best to add some extra padding (10%) to allow a smooth transition from the end of the sequence back to the beginning. Remember the FFT algorithm assumes the function is periodic. nSeries  Number of time sequences to be filtered Returns: the new object.

void ObitTimeFilter2Freq (  ObitTimeFilter *  in  )

Public: Compute frequency series. A linear interpolation between the last valid point and the first valid point is made to reduce the wraparound edge effects. Parameters: in  Object with TimeFilter structures.

void ObitTimeFilter2Time (  ObitTimeFilter *  in  )

Public: Compute Time series. Parameters: in  Object with TimeFilter structures.

void ObitTimeFilterClassInit (  void   )

Public: Class initializer.

void ObitTimeFilterFilter (  ObitTimeFilter *  in, gint  seriesNo, ObitTimeFilterType  type, gfloat *  parms, ObitErr *  err )

Public: Apply Filter to Frequency series. Following Filters are supported: OBIT_TimeFilter_LowPass - Zeroes frequencies above a fraction, parms[0], of the highest. OBIT_TimeFilter_HighPass - Zeroes frequencies below a fraction, parms[0], of the highest. Parameters: in  Object with TimeFilter structures. seriesNo  Which time/frequency series to apply to (0-rel), <0 => all type  Filter type to apply *parm  Parameters for filter, meaning depends on type. err  Error stack

gconstpointer ObitTimeFilterGetClass (  void   )

Public: ClassInfo pointer. Returns: pointer to the class structure.

void ObitTimeFilterResize (  ObitTimeFilter *  in, gint  nTime )

Public: Resize arrays. Parameters: in  ObitTimeFilter to resize. nTime  Number of times in arrays to be filtered It is best to add some extra padding (10%) to allow a smooth transition from the end of the sequence back to the beginning. Remember the FFT algorithm assumes the function is periodic.

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