CmdSelect Class Reference

Select parts of hierarchical data using path, quantity, elevation angle and PRF mode as selection criteria. More...

Inheritance diagram for CmdSelect:

Collaboration diagram for CmdSelect:

Public Member Functions
	CmdSelect (const CmdSelect &cmd)
virtual void	exec () const override
	Run the command with current parameter values.
virtual void	parametersToStreamFOO (std::ostream &ostr, const std::string &indent=" ") const
virtual void	parameterKeysToStreamFOO (std::ostream &ostr) const
Public Member Functions inherited from BasicCommand
	BasicCommand (const std::string &name, const std::string &description)
	Constructor.
	BasicCommand (const BasicCommand &cmd)
	Copy constructor.
Public Member Functions inherited from BeanCommand< BeanLike >
	BeanCommand (const std::string &name, const std::string &description)
	Constructor.
	BeanCommand (const BeanCommand &cmd)
	Copy constructor.
	BeanCommand (BeanLike &b)
	Constructor wrapping an existing bean.
virtual const bean_t &	getBean () const
	Returns the wrapped bean.
virtual bean_t &	getBean ()
	Returns the wrapped bean.
const std::string &	getName () const final
	Returns the command name.
const std::string &	getDescription () const final
	Returns the command description.
virtual const drain::ReferenceMap &	getParameters () const
	Returns the command parameters.
Public Member Functions inherited from Command
	Command (const Command &cmd)
	Copy constructor.
virtual void	setParameters (const std::string &args) final
template<class T >
void	setParameters (const T &args)
	Sets parameters from argument.
template<class T >
void	setParameter (const std::string &key, const T &value)
	Set a value to a single parameter.
bool	hasParameters () const
	Returns true if this command has parameters.
virtual void	run (const std::string &params="") final
	Description of result, comparable to a return type of a function. ?
virtual void	update ()
	Optional method for preparing command to execution.
Command &	addSection (int i)
	Marks this command as belonging to section i.
const std::string &	getLastParameters () const
	Returns the parameters from the last execution.
virtual void	getRelatedCommands (std::ostream &ostr=std::cout) const
	Writes related command names to stream.
void	linkRelated (const std::string &cmdKey) const
	Add related command(s), to appear in help after "See-also:" phrase.
virtual void	parametersToStream (std::ostream &ostr, const std::string &indent=" ") const
	By default, the "true", technical parameters.
virtual void	parameterKeysToStream (std::ostream &ostr) const
	Writes parameter keys to stream.
void	parameterKeysToStream (std::ostream &ostr, const std::list< std::string > &list, char sep=',') const
	Writes parameter keys to stream.
Public Member Functions inherited from Contextual
	Contextual ()
	Sets internal contextPtr to NULL.
	Contextual (const Contextual &src)
	Copies base context (even null) of the source. Notice that the actual instance may be of derived class.
	Contextual (Context &ctx)
	Copies internal contextPtr.
template<class C >
void	setContext ()
	Sets internal contextPtr to the static source.
void	setExternalContext (Context &ctx)
	Sets internal contextPtr to outside target.
bool	contextIsSet () const
	True, if contextPtr has been set.
template<class T = Context>
T &	getContext () const
	If context has been set, returns it through a cast to base class Context.

Additional Inherited Members
Public Types inherited from BeanCommand< BeanLike >
typedef BeanLike	bean_t
	The bean type.
Public Types inherited from Command
typedef int	cmd_section_type
Static Public Member Functions inherited from Contextual
template<class T >
static Cloner< Context, T > &	getCloner ()
	Returns the object cloner.
Public Attributes inherited from BeanCommand< BeanLike >
BeanLike	bean
	The wrapped bean instance.
Public Attributes inherited from Command
cmd_section_type	section = 1
	Section bitmask; zero means hidden from help.
Static Public Attributes inherited from Command
static const SprinterLayout	cmdArgLayout = {",", "?", "=", ""}
	Layout flag for command argument handling.
Protected Member Functions inherited from CmdBaseSelective
	CmdBaseSelective (const std::string &name, const std::string &description)
	CmdBaseSelective (const CmdBaseSelective &cmd)
Protected Member Functions inherited from BeanCommand< BeanLike >
virtual drain::ReferenceMap &	getParameters () final
Protected Attributes inherited from CmdBaseSelective
DataSelector	mySelector
Protected Attributes inherited from Command
std::set< std::string >	relatedCommands
	Set of related command keys shown in help.
std::string	lastParameters
	String record of the last argument(s) passed.
Protected Attributes inherited from Contextual
Context *	contextPtr
	Pointer to the current context; nullptr if not set.

Detailed Description

Select parts of hierarchical data using path, quantity, elevation angle and PRF mode as selection criteria.

This command determines the data to be applied in subsequent input read or product generation commands.

In Rack, many operations implictly select a subset of available data instead of using it all. For example, in computing a Pseudo CAPPI image, DBZH data from single-PRF sweeps is used by default.

Synopsis

Remarks on the options:

• path argument defines a path segment to be matched, with desired index ranges (example: dataset2:4/data3:8 )
• in path argument, a leading slash fixes the matching to the root (example: /dataset:/data: ), otherwise the tail part is matched
• quantity argument accepts a list of strings separated by semicolon ':'
• each item in a quantity argument list can be a literal string like DBZH or a regular experession like ^DBZ[HV]?$

See examples further below.

This option is useful in selecting data for:

• partial reading or writing a large file (see File input and output ), or saving selected images (PNG, GeoTIFF, PPM; see Image processing ).
• selecting data for anomaly detection and removal (see Anomaly Detection and Removal (AnDRe) ).
• computing a meteorological product (see Meteorological products ).
• compositing (see Cartesian conversions and composites )

In addition, these explicit data modification options use the same syntax

• --keep - prune internal data structure such that only the selected part remains (what , where and how groups are preserved automatically).
• --delete - remove parts of internal data structure – single attributes or large subtrees.

The following command lines illustrate usage of --select in product generation and image output.

# For a Pseudo CAPPI product, change default input selection
rack volume.h5 --select 'quantity=^TH$,elangle=1.5:10,count=3' --pCappi 1500 -o pCappi-TH-1500m.h5
 
# For image output, select DBZH  
rack volume.h5 --select elangle=1.5,quantity=DBZH -o volume-DBZH.png
 
# For image output, select VRAD of the lowest dual-PRF scan 
rack volume.h5 --select quantity=VRAD:VRADH,order=ELANGLE:MIN,prf=DOUBLE -o volume-VRAD.png
 
# For image output, select ZDR of the highest single-PRF scan 
rack volume.h5 --select quantity=ZDR,count=1,order=ELANGLE:MAX,prf=SINGLE -o volume-ZDR.png
 
# For single-image output, select DBZH of the lowest scan (from 90 6.5 2.4 1.8 1.2 0.59)
rack volume.h5 --select quantity=DBZH,order=ELANGLE:MIN -o volume-DBZH2.png
 
# For single-image output, select dBZ - preferably total dBZ - of the highest scan (from 90 6.5 2.4 1.8 1.2 0.59)
rack volume.h5 --select quantity=TH:TV:T:DBZH:DBZ,order=ELANGLE:MAX -o volume-DBZH3.png
 

The following examples are less realistic than those above, but are used in unit testing of the program code. ( You may wish to change output file extension from .txt to .h5 ).

# Index range: select dataset3, including its subgroups. 
rack volume.h5 --select /dataset3 -o volume-select.txt
 
# Index range: select DATASET groups with index 2...5, including subgroups. 
rack volume.h5 --select /dataset2:5 -o volume-select.txt
 
# Index range test: select DATASET groups with index 3 at least.
rack volume.h5 --select /dataset3: -o volume-select.txt
 
# Index range test: select DATASET groups with index 3 at largest. 
rack volume.h5 --select /dataset:3 -o volume-select.txt
 
# For text output, select paths of elevations of at least 6.0 degrees 
rack volume.h5 --select elangle=6.0 -o volume-select.txt
 
# For text output, select paths of elevations up to 6.0 degrees 
rack volume.h5 --select elangle=:6.0 -o volume-select.txt
 
# For text output, select 'where' groups of 3 lowest elevations from 0.5 degrees upwards 
rack volume.h5 --select where,elangle=0.5:90.0,count=3 -o volume-select.txt
 
# For text output, select 'what' and 'where' groups of elevations from 0.5 to 6.0 degrees
rack volume.h5 --select 'what|where,elangle=0.5:6' -o volume-select.txt
 
# Select a unique quality field
rack volume.h5 --select quantity=CLASS-ETOP -o volume-select.txt
 
# Select all QIND fields
rack volume.h5 --select quantity=QIND -o volume-select.txt
 
# Select global (dataset-level) QIND fields
rack volume.h5 --select quantity=/QIND -o volume-select.txt
 
# Select quantity-specific (data-level) QIND fields
rack volume.h5 --select quantity=.+/QIND -o volume-select.txt
 
# Select quantity-specific (data-level) QIND field
rack volume.h5 --select quantity=DBZ-SLOPE-SMOOTH/QIND -o volume-select.txt
 
# Select non-existing quantity-specific QIND field
rack volume.h5 --select quantity=HGHT/QIND -o volume-select.txt
 

See also

rack::CmdDelete

rack::CmdKeep

rack::CmdSetODIM

rack::CmdSelect (code)

rack::DataSelector (code)

Member Function Documentation

exec()

virtual void exec ( ) const

inlineoverridevirtual

Run the command with current parameter values.

Reimplemented from Command.

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The documentation for this class was generated from the following file:

• src/main/commands.cpp