org.das2.qds

Class ConstantDataSet

java.lang.Object

org.das2.qds.ConstantDataSet

All Implemented Interfaces:

QDataSet

public final class ConstantDataSet
extends java.lang.Object
implements QDataSet

efficient dataset that has no properties and one value. This can be used as a marker interface too, where the client can inspect the type and just get the valid value once. See also ReplicateDataSet and TagGenDataSet

Field Summary

Fields inherited from interface org.das2.qds.QDataSet

BIN_MAX, BIN_MIN, BIN_MINUS, BIN_PLUS, BINS_0, BINS_1, BUNDLE_0, BUNDLE_1, BUNDLE_2, BUNDLE_3, CACHE_TAG, CADENCE, CONTEXT_0, COORDINATE_FRAME, DEFAULT_FILL_VALUE, DELTA_MINUS, DELTA_PLUS, DEPEND_0, DEPEND_1, DEPEND_2, DEPEND_3, DEPENDNAME_0, DEPENDNAME_1, DESCRIPTION, ELEMENT_DIMENSIONS, ELEMENT_LABEL, ELEMENT_NAME, FILL_VALUE, FORMAT, JOIN_0, LABEL, MAX_HIGH_RANK, MAX_PLANE_COUNT, MAX_RANK, MAX_UNIT_BUNDLE_COUNT, METADATA, METADATA_MODEL, MIN_WAVEFORM_LENGTH, MONOTONIC, NAME, NOTES, PLANE_0, QUBE, RENDER_TYPE, SCALE_TYPE, SOURCE, START_INDEX, TITLE, TYPICAL_MAX, TYPICAL_MIN, UNITS, USER_PROPERTIES, VALID_MAX, VALID_MIN, VALUE_BINS_MIN_MAX, VALUE_COORDINATE_FRAME_COMPLEX_NUMBER, VALUE_METADATA_MODEL_ISTP, VALUE_METADATA_MODEL_SPASE, VALUE_RENDER_TYPE_COMPOSITE_IMAGE, VALUE_RENDER_TYPE_DIGITAL, VALUE_RENDER_TYPE_EVENTS_BAR, VALUE_RENDER_TYPE_NNSPECTROGRAM, VALUE_RENDER_TYPE_SERIES, VALUE_SCALE_TYPE_LINEAR, VALUE_SCALE_TYPE_LOG, VERSION, WEIGHTS

Constructor Summary

Constructors

Constructor and Description
ConstantDataSet(int len, double value)

Method Summary

Modifier and Type	Method and Description
<T> T	capability(java.lang.Class<T> clazz) return null or an object implementing the capability for the given interface For example:
int	length() return the length of the first dimension
int	length(int i) return the length of the second dimension, for the ith element of the first dimension.
int	length(int i, int j) return the length of the third dimension, for the ith element of the first dimension and jth element of the second dimension.
int	length(int i, int j, int k) return the length of the fourth dimension for the ith, jth and kth elements of the first three dimensions.
java.lang.Object	property(java.lang.String name) accessor for properties attached to the dataset.
java.lang.Object	property(java.lang.String name, int i) accessor for properties attached to the dataset's first index.
int	rank() returns the rank of the dataset, which is the number of indeces used to access data.
QDataSet	slice(int i) return a dataset that is a slice of this dataset, slicing on the zeroth dimension.
QDataSet	trim(int start, int end) return a dataset that is a subset of this dataset.
double	value() rank 0 accessor.
double	value(int i0) rank 1 accessor.
double	value(int i0, int i1) rank 2 accessor.
double	value(int i0, int i1, int i2) rank 3 accessor.
double	value(int i0, int i1, int i2, int i3) rank 4 accessor.

Methods inherited from class java.lang.Object

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

Constructor Detail

ConstantDataSet

public ConstantDataSet(int len,
                       double value)

Method Detail

rank

public int rank()

Description copied from interface: QDataSet

returns the rank of the dataset, which is the number of indeces used to access data. Only rank 0, 1, 2, 3, and 4 datasets are supported in the interface. When a dataset's rank is 5 or greater, it should implement the HighRankDataSet interface which affords a slice operation to reduce rank.

Specified by:

rank in interface QDataSet

Returns:

the rank, or number of indeces used to access data.

value

public double value()

Description copied from interface: QDataSet

rank 0 accessor.

Specified by:

value in interface QDataSet

Returns:

the value, see the property UNITS to interpret this.

value

public double value(int i0)

Description copied from interface: QDataSet

rank 1 accessor.

Specified by:

value in interface QDataSet

Parameters:

i0 - the index

Returns:

the value, see the property UNITS to interpret this.

value

public double value(int i0,
                    int i1)

Description copied from interface: QDataSet

rank 2 accessor.

Specified by:

value in interface QDataSet

Parameters:

i0 - the index

i1 - the index

Returns:

the value, see the property UNITS to interpret this.

value

public double value(int i0,
                    int i1,
                    int i2)

Description copied from interface: QDataSet

rank 3 accessor.

Specified by:

value in interface QDataSet

Parameters:

i0 - the index

i1 - the index

i2 - the index

Returns:

the value, see the property UNITS to interpret this.

value

public double value(int i0,
                    int i1,
                    int i2,
                    int i3)

Description copied from interface: QDataSet

rank 4 accessor.

Specified by:

value in interface QDataSet

Parameters:

i0 - the index

i1 - the index

i2 - the index

i3 - the index

Returns:

the value, see the property UNITS to interpret this.

property

public java.lang.Object property(java.lang.String name)

Description copied from interface: QDataSet

accessor for properties attached to the dataset. See final static members for example properties.

Specified by:

property in interface QDataSet

Parameters:

name - property name, such as "DEPEND_0" or "UNITS"

Returns:

the value

See Also:

QDataSet.DEPEND_0, QDataSet.UNITS

property

public java.lang.Object property(java.lang.String name,
                                 int i)

Description copied from interface: QDataSet

accessor for properties attached to the dataset's first index. These properties override (or shadow) properties attached to the dataset, and often implementations will simply return the result of the no-index accessor. Note: properties of higher dimension are accessible only by slicing.

Specified by:

property in interface QDataSet

Parameters:

name - property name, such as "DEPEND_0" or "UNITS"

i - the index

Returns:

the value

See Also:

QDataSet.DEPEND_0, QDataSet.UNITS

length

public int length()

Description copied from interface: QDataSet

return the length of the first dimension

Specified by:

length in interface QDataSet

Returns:

the length of the first dimension

length

public int length(int i)

Description copied from interface: QDataSet

return the length of the second dimension, for the ith element of the first dimension. Note if there are zero elements in the first dimension, but this is a QUBE, then this should not throw an IndexOutOfBoundsException.

Specified by:

length in interface QDataSet

Parameters:

i - the index

Returns:

the length of the second dimension at index i.

length

public int length(int i,
                  int j)

Description copied from interface: QDataSet

return the length of the third dimension, for the ith element of the first dimension and jth element of the second dimension.

Specified by:

length in interface QDataSet

Parameters:

i - the index

j - the index

Returns:

the length of the third dimension at index i.

length

public int length(int i,
                  int j,
                  int k)

Description copied from interface: QDataSet

return the length of the fourth dimension for the ith, jth and kth elements of the first three dimensions.

Specified by:

length in interface QDataSet

Parameters:

i - the index

j - the index

k - the index

Returns:

the length of the fourth dimension for the ith, jth and kth elements of the first three dimensions.

slice

public QDataSet slice(int i)

Description copied from interface: QDataSet

return a dataset that is a slice of this dataset, slicing on the zeroth dimension. A slice will be the elements at this index, for example if this dataset is a rank 2 dataset flux(Time,Energy) then the slice of this will be a rank 1 dataset flux(Energy). The result of any slice will be a qube.

Specified by:

slice in interface QDataSet

Parameters:

i - the index to slice at

Returns:

the rank n-1 QDataSet at index i.

trim

public QDataSet trim(int start,
                     int end)

Description copied from interface: QDataSet

return a dataset that is a subset of this dataset. For example:

 
    ds= DDataSet.createRank1(100);
    QDataSet trim= ds.trim(50,60);
    assert( trim.length()==10 );
 
 

Specified by:

trim in interface QDataSet

Parameters:

start - the first index to be included in the new dataset.

end - the exclusive index indicating the last index.

Returns:

a QDataSet with the same rank but fewer elements.

capability

public <T> T capability(java.lang.Class<T> clazz)

Description copied from interface: QDataSet

return null or an object implementing the capability for the given interface For example:

ds= DDataSet.createRank1(100);
WriteCapability write= ds.capability( WriteCapability.class );
write.putValue( 99, -1e31 );

This allows operations to be performed efficiently. Note there is no WriteCapability class, this is just an example.

Specified by:

capability in interface QDataSet

Type Parameters:

T - a capability

Parameters:

clazz - the class, such as WriteCapability.class

Returns:

the implementing class, or null (Jython None) if the capability is not provided.