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
  AVERAGE_TYPE, BIN_MAX, BIN_MAX_NAME, BIN_MIN, BIN_MIN_NAME, BIN_MINUS, BIN_MINUS_NAME, BIN_PLUS, BIN_PLUS_NAME, BINS_0, BINS_1, BUNDLE_0, BUNDLE_1, BUNDLE_2, BUNDLE_3, CACHE_TAG, CADENCE, CONTEXT_0, CONTEXT_1, COORDINATE_FRAME, DEFAULT_FILL_VALUE, DELTA_MINUS, DELTA_MINUS_NAME, DELTA_PLUS, DELTA_PLUS_NAME, 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, LIMIT_HUGE_DATASET, 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_AVERAGE_TYPE_GEOMETRIC, VALUE_AVERAGE_TYPE_LINEAR, VALUE_AVERAGE_TYPE_MOD24, VALUE_AVERAGE_TYPE_MOD360, VALUE_AVERAGE_TYPE_MODPI, VALUE_AVERAGE_TYPE_MODTAU, VALUE_AVERAGE_TYPE_NONE, VALUE_BINS_MIN_MAX, VALUE_BINS_MIN_MAX_INCLUSIVE, 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_RENDER_TYPE_TRIANGLE_MESH, VALUE_SCALE_TYPE_LINEAR, VALUE_SCALE_TYPE_LOG, VERSION, WEIGHTS

Constructor Summary

Constructors
Constructor and Description

ConstantDataSet(int len, double value)
create a rank 1 dataset of the given length.

Constructors
Constructor and Description
`ConstantDataSet(int len, double value)` create a rank 1 dataset of the given length.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
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:
`static ConstantDataSet`	`create(double value, int[] qube)` create a constant dataset with the value and having the dimensions given in qube.
`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.
`java.lang.String`	`svalue()` rank 0 accessor which provides the string value
`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)
```
    create a rank 1 dataset of the given length.
    
    Parameters:
    
    len -
    
    value -
- Method Detail
  - create
```
public static ConstantDataSet create(double value,
                                     int[] qube)
```
    create a constant dataset with the value and having the dimensions given in qube.
    
    Parameters:
    
    value - the value for the dataset.
    
    qube - number of elements in each dimension
    
    Returns:
    
    the dataset.
  - 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.
  - svalue
```
public java.lang.String svalue()
```
    Description copied from interface: QDataSet
    
    rank 0 accessor which provides the string value
    
    Specified by:
    
    svalue 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. Note the index must be positive. Negative indices, referenced from the end of the dataset, are not supported.
    
    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 );
 
 
```
    Note start and end must be positive. Negative indices, referenced from the end of the dataset, are not supported here.
    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.
    
    See Also:
    
    LongWriteAccess, LongReadAccess, FloatReadAccess

Class ConstantDataSet

Field Summary

Fields inherited from interface org.das2.qds.QDataSet

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ConstantDataSet

Method Detail

create

rank

value

svalue

value

value

value

value

property

property

length

length

length

length

slice

trim

capability