MSDerivedValues.h

Classes

MSDerivedValues -- MSDerivedValues calculates values derived from a MS (full description)

class MSDerivedValues

Interface

Public Members

MSDerivedValues()

~MSDerivedValues()

MSDerivedValues(const MSDerivedValues& other)

MSDerivedValues& operator=(const MSDerivedValues& other)

Int setAntennas(const ROMSAntennaColumns& ac)

MSDerivedValues& setAntennaPositions(const Vector<MPosition>& antPosition)

MSDerivedValues& setObservatoryPosition(const MPosition& obsPosition)

MSDerivedValues& setAntennaMount(const Vector<String>& mount)

MSDerivedValues& setEpoch(const MEpoch& time)

MSDerivedValues& setFieldCenter(const MDirection& fieldCenter)

MSDerivedValues& setAntenna(Int antenna)

MSDerivedValues& setVelocityFrame(MRadialVelocity::Types vType)

Double hourAngle()

Double parAngle()

const MDirection& azel()

const MEpoch& last()

const MRadialVelocity& obsVel()

Private Members

void init()

Description

Review Status

Date Reviewed:: yyyy/mm/dd

Prerequisite

MeasurementSet
SomeOtherClass
some concept

Etymology

MSDerivedValues calculates values derived from those in a MS

Synopsis

MSDerivedValues is a class that computes values derived from those present in a MeasurementSet. E.g., calculate feed position angles on the sky from time, antenna positions and feed characteristics.

Example

    // calculate the parallactic angle and the observatory velocity for the
    // first time and first source in the MS.
    // set up 
    MSDerivedValues msd;
    MS myMS("myMS");
    ROMSColumns msc(myMS);
    msd.setAntennas(msc.antenna());
    MEpoch ep=MS::epochMeasure(msc.time());
    ep.set(MVEpoch(Quantity(msc.time()(0),"s")));
    msd.setEpoch(ep);
    MDirection dir=MS::directionMeasure(msc.field().phaseDir());
    dir.set(MVDirection(Vector<Double>(msc.field().phaseDir()(0))));
    msd.setFieldCenter(dir);
    msd.setVelocityFrame(MRadialVelocity::LSRK);
    // now we are ready for the calculations:
    Double parAngle = msd.parangle();
    MRadialVelocity observatoryVel = msd.obsVel();

Motivation

Values derived from those in a MS are needed in various places, e.g., for plotting purposes. This class combines the commonly needed calculations in one place.

Thrown Exceptions

To Do

the interface should be less cumbersome
probably needs speeding up

Member Description

MSDerivedValues()

~MSDerivedValues()

MSDerivedValues(const MSDerivedValues& other)

Copy constructor, this will initialize with other's MS

MSDerivedValues& operator=(const MSDerivedValues& other)

Assignment, this will initialize with other's MS

Int setAntennas(const ROMSAntennaColumns& ac)

Set antenna position from an antenna table Returns the number of antennas. Also sets the observatory position to the average of the antenna positions.

MSDerivedValues& setAntennaPositions(const Vector<MPosition>& antPosition)

Set antenna positions, index in vector is antenna number for calls below.

MSDerivedValues& setObservatoryPosition(const MPosition& obsPosition)

Set the observatory position. Note that setAntennas will reset this.

MSDerivedValues& setAntennaMount(const Vector<String>& mount)

Set antenna mounts, should have same number of entries as antPosition in setAntennaPosition

MSDerivedValues& setEpoch(const MEpoch& time)

Set epoch

MSDerivedValues& setFieldCenter(const MDirection& fieldCenter)

Set field center

MSDerivedValues& setAntenna(Int antenna)

Set antenna index, sets the position reference for the conversions. Use -1 to set the reference frame to the observatory position.

MSDerivedValues& setVelocityFrame(MRadialVelocity::Types vType)

Set the velocity frame type (e.g., MRadialVelocity::LSRK)

Double hourAngle()

get hour angle

Double parAngle()

get parallactic angle

const MDirection& azel()

get azimuth & elevation

const MEpoch& last()

get LAST for given time, antenna

const MRadialVelocity& obsVel()

get observatory radial velocity for given epoch, position and direction

void init()

initialize data