org.das2.qds.util

Class LSpec

java.lang.Object

org.das2.qds.util.LSpec

public class LSpec
extends java.lang.Object

Form a rank 2 dataset with L and Time for tags by identifying monotonic sweeps in two rank 1 datasets, and interpolating along the sweep.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DIR_BOTH include both sweeps
static int	DIR_INWARD just the inward sweeps
static int	DIR_OUTWARD just the outward sweeps
static java.lang.String	USER_PROP_SWEEPS identifies the sweep of each record

Method Summary

Modifier and Type	Method and Description
static QDataSet	identifySweeps(QDataSet lds, int dir) identify monotonically increasing or decreasing segments of the dataset.
static QDataSet	rebin(QDataSet tlz, QDataSet lgrid, int dir) alternate, convenient interface which where tlz is a bundle of buckshot data (T,L,Z)
static QDataSet	rebin(QDataSet lds, QDataSet zds, QDataSet lgrid) rebin the datasets to rank 2 dataset ( time, LShell ), by interpolating along sweeps.
static QDataSet	rebin(QDataSet lds, QDataSet zds, QDataSet lgrid, int dir) rebin the datasets to rank 2 dataset ( time, LShell ), by interpolating along sweeps.
static QDataSet	rebin(QDataSet tt, QDataSet lds, QDataSet zds, QDataSet tspace, QDataSet lgrid, int dir) alternate algorithm following Brian Larson's algorithm that rebin the datasets to rank 2 dataset ( time, LShell ), by interpolating along sweeps.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

USER_PROP_SWEEPS

public static final java.lang.String USER_PROP_SWEEPS

identifies the sweep of each record

See Also:

Constant Field Values

DIR_INWARD

public static int DIR_INWARD

just the inward sweeps

DIR_OUTWARD

public static int DIR_OUTWARD

just the outward sweeps

DIR_BOTH

public static int DIR_BOTH

include both sweeps

Method Detail

identifySweeps

public static QDataSet identifySweeps(QDataSet lds,
                                      int dir)

identify monotonically increasing or decreasing segments of the dataset.

Parameters:

lds - the dataset which sweeps back and forth, such as LShell or MagLat (or a sine wave for testing).

dir - 0=both 1=outward 2= inward

Returns:

rank 2 data set of sweep indeces, dim0 is sweep number, dim1 is two-element [ start, end(inclusive) ].

rebin

public static QDataSet rebin(QDataSet lds,
                             QDataSet zds,
                             QDataSet lgrid)

rebin the datasets to rank 2 dataset ( time, LShell ), by interpolating along sweeps. This dataset has the property "sweeps", which is a dataset that indexes the input datasets.

Parameters:

lds - rank 1 dataset of length N

zds - rank 1 dataset of length N, indexed along with lds

lgrid - rank 1 dataset indicating the dim 1 tags for the result dataset.

Returns:

a rank 2 dataset, with one column per sweep, interpolated to lgrid

rebin

public static QDataSet rebin(QDataSet tlz,
                             QDataSet lgrid,
                             int dir)

alternate, convenient interface which where tlz is a bundle of buckshot data (T,L,Z)

Parameters:

tlz - x,y,z (T,L,Z) bundle of Z values collected along inward and outward sweeps of L in time.

lgrid - desired uniform grid of L values.

dir - =1 increasing (outward) only, =-1 decreasing (inward) only, 0 both.

Returns:

a rank 2 dataset, with one column per sweep, interpolated to lgrid

rebin

public static QDataSet rebin(QDataSet tt,
                             QDataSet lds,
                             QDataSet zds,
                             QDataSet tspace,
                             QDataSet lgrid,
                             int dir)

alternate algorithm following Brian Larson's algorithm that rebin the datasets to rank 2 dataset ( time, LShell ), by interpolating along sweeps. This dataset has the property "sweeps", which is a dataset that indexes the input datasets.

Parameters:

lds - The L values corresponding to y axis position, which should be a function of time.

tt - The Time values corresponding to x axis position. If null, then use lds.property(QDataSet.DEPEND_0).

zds - the Z values corresponding to the parameter we wish to organize

tspace - rank 0 cadence, such as dataset('9 hr')

lgrid - rank 1 data is the grid points, such as linspace( 2.,8.,30 )

dir - =1 increasing (outward) only, =-1 decreasing (inward) only, 0 both

Returns:

a rank 2 dataset, with one column per sweep, interpolated to lgrid

rebin

public static QDataSet rebin(QDataSet lds,
                             QDataSet zds,
                             QDataSet lgrid,
                             int dir)

rebin the datasets to rank 2 dataset ( time, LShell ), by interpolating along sweeps. This dataset has the property "sweeps", which is a dataset that indexes the input datasets.

Parameters:

lds - rank 1 dataset of length N

zds - rank 1 dataset of length N, indexed along with lds

lgrid - rank 1 dataset indicating the dim 1 tags for the result dataset.

dir - =1 increasing (outward) only, =-1 decreasing (inward) only, 0 both

Returns:

a rank 2 dataset, with one column per sweep, interpolated to lgrid