Package noaa.coastwatch.util

Class SubsetGrid

java.lang.Object

noaa.coastwatch.util.MetadataContainer

noaa.coastwatch.util.DataVariable

noaa.coastwatch.util.Grid

noaa.coastwatch.util.SubsetGrid

All Implemented Interfaces:

Cloneable, ValueSource

public class SubsetGrid
extends Grid

The SubsetGrid class uses an existing Grid object to provide a subset view of its data. For example, if the original grid has dimensions (1024,1024) and the subset is defined to show only a small section starting at (100,100) of dimensions (512,512), then accessing location (0,0) in the subset is the same as accessing location (100,100) in the original grid. All other properties of the original grid are the same.

Since:

3.1.7

Author:

Peter Hollemans

Nested Class Summary

Nested classes/interfaces inherited from class noaa.coastwatch.util.DataVariable

DataVariable.AccessType

Field Summary

Fields inherited from class noaa.coastwatch.util.Grid

COL, COLS, ROW, ROWS

Fields inherited from class noaa.coastwatch.util.DataVariable

data, dims, isUnsigned, lookup, unsignedType

Constructor Summary

Constructors

Constructor	Description
SubsetGrid(Grid grid, int[] start, int[] dims)	Creates a new subset based on the specified grid and parameters.

Method Summary

Modifier and Type	Method	Description
Object	getData()	Gets the variable data array.
Object	getData(int[] start, int[] count)	Gets a subset of grid data values.
double	getValue(int index)	Reads a scaled data value.
double	getValue(int row, int col)	Reads a scaled data value with no navigation.
double	getValue(DataLocation loc)	Reads a scaled data value with navigation.
double	interpolate(DataLocation loc)	Reads an interpolated data value.
void	setValue(int index, double val)	Writes a scaled data value.
void	setValue(int row, int col, double val)	Writes a scaled data value with no navigation.
void	setValue(DataLocation loc, double val)	Writes a scaled data value with navigation.

Methods inherited from class noaa.coastwatch.util.Grid

arraycopy, checkSubset, getNavigation, getSubset, getTilingScheme, main, navigate, setData, setNavigation

Methods inherited from class noaa.coastwatch.util.DataVariable

convertUnits, dispose, format, format, format, getClassBits, getDataClass, getDecimals, getDimensions, getFormat, getLongName, getMissing, getName, getOptimalStride, getRank, getScaling, getStatistics, getStatistics, getStatistics, getStatistics, getUnits, getUnsigned, getValue, getValues, setAccessHint, setAccessType, setData, setFormat, setLongName, setLookup, setMissing, setName, setUnits, setUnsigned, setValue, toString

Methods inherited from class noaa.coastwatch.util.MetadataContainer

clone, getMetadataMap

Methods inherited from class java.lang.Object

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

Constructor Details

SubsetGrid

public SubsetGrid(Grid grid,
 int[] start,
 int[] dims)

Creates a new subset based on the specified grid and parameters.

Parameters:

grid - the grid to subset.

start - the starting data location for the subset as [row, column].

dims - the subset dimensions as [rows, columns].

Method Details

setValue

public void setValue(int row,
 int col,
 double val)

Description copied from class: Grid

Writes a scaled data value with no navigation. The data value is scaled according to the scaling factor and offset and written to the data array. No navigation transform is applied to correct the data location.

Overrides:

setValue in class Grid

Parameters:

row - the data location row.

col - the data location column.

val - the data value as a double. If the data value is Double.NaN and the missing value is non-null, the missing value is written to the array.

See Also:

• Grid.setValue(DataLocation,double)

getValue

public double getValue(int row,
 int col)

Description copied from class: Grid

Reads a scaled data value with no navigation. The data value is read from the data array and scaled according to the scaling factor and offset. No navigation transform is applied to correct the data location.

Overrides:

getValue in class Grid

Parameters:

row - the data location row.

col - the data location column.

Returns:

the scaled data value as a double. The Double.NaN value is used if the data value is missing or data coordinate is not valid.

See Also:

• Grid.getValue(DataLocation)

setValue

public void setValue(DataLocation loc,
 double val)

Description copied from class: Grid

Writes a scaled data value with navigation. The data value is scaled according to the scaling factor and offset and written to the data array. The navigation transform is applied to correct the data location prior to writing the data value.

Overrides:

setValue in class Grid

Parameters:

loc - the data location. If the location does not navigate to a valid data coordinate, no value is written.

val - the data value as a double. If the data value is Double.NaN and the missing value is non-null, the missing value is written to the array.

See Also:

• Grid.setValue(int,int,double)

getValue

public double getValue(DataLocation loc)

Description copied from class: Grid

Reads a scaled data value with navigation. The data value is read from the data array and scaled according to the scaling factor and offset. The navigation transform is applied to correct the data location prior to reading the data value.

Specified by:

getValue in interface ValueSource

Overrides:

getValue in class Grid

Parameters:

loc - the data value location.

Returns:

the scaled data value as a double. The Double.NaN value is used if the data value is missing or navigated data coordinate is not valid.

See Also:

• Grid.getValue(int,int)

setValue

public void setValue(int index,
 double val)

Description copied from class: DataVariable

Writes a scaled data value. The data value is scaled according to the scaling factor and offset and written to the data array.

Overrides:

setValue in class DataVariable

Parameters:

index - the index into the data array.

val - the data value as a double. If the data value is Double.NaN and the missing value is non-null, the missing value is written to the array.

See Also:

• DataVariable.setValue(DataLocation,double)

getValue

public double getValue(int index)

Description copied from class: DataVariable

Reads a scaled data value. The data value is read from the data array and scaled according to the scaling factor and offset.

Overrides:

getValue in class DataVariable

Parameters:

index - the index into the data array.

Returns:

the scaled data value as a double. The Double.NaN value is used if the data value is missing.

See Also:

• DataVariable.getValue(DataLocation)

interpolate

public double interpolate(DataLocation loc)

Description copied from class: DataVariable

Reads an interpolated data value.

Overrides:

interpolate in class Grid

Parameters:

loc - the data value location.

Returns:

the scaled data value as a double. The Double.NaN value is used if the data value is missing.

See Also:

• DataVariable.getValue(int)
• DataVariable.getValue(DataLocation)

getData

public Object getData()

Description copied from class: DataVariable

Gets the variable data array. The returned data is read-only -- the result of attempting to set values in the data is undefined.

Overrides:

getData in class DataVariable

getData

public Object getData(int[] start,
 int[] count)

Description copied from class: Grid

Gets a subset of grid data values. This method is similar to Grid.getData(int[], int[]), but retrieves only a subset of data values in the raw, unscaled form.

Overrides:

getData in class Grid

Parameters:

start - the subset starting [row, column].

count - the subset dimension [rows, columns].

Returns:

an array containing the unscaled data values.

See Also:

• DataVariable.getData()