Parses the command line for parameters and holds user-specified parameters. More...

Public Types
typedef std::map< std::string, std::map< std::string, void()(const util::ParamData &, const void , void *)> >	FunctionMapType
	Map for functions and types. More...

Static Public Member Functions
static void	Add (util::ParamData &&d)
	Adds a parameter to the hierarchy; use the PARAM_*() macros instead of this (i.e. More...

static std::map< char, std::string > &	Aliases ()
	Return a modifiable list of aliases that CLI knows about. More...

static void	ClearSettings ()
	Clear all of the settings, removing all parameters and function mappings. More...

template < typename T >
static T &	GetParam (const std::string &identifier)
	Get the value of type T found while parsing. More...

template < typename T >
static std::string	GetPrintableParam (const std::string &identifier)
	Cast the given parameter of the given type to a short, printable std::string, for use in status messages. More...

template < typename T >
static T &	GetRawParam (const std::string &identifier)
	Get the raw value of the parameter before any processing that GetParam() might normally do. More...

static CLI &	GetSingleton ()
	Retrieve the singleton. More...

static bool	HasParam (const std::string &identifier)
	See if the specified flag was found while parsing. More...

static void	MakeInPlaceCopy (const std::string &outputParamName, const std::string &inputParamName)
	Given two (matrix) parameters, ensure that the first is an in-place copy of the second. More...

static std::map< std::string, util::ParamData > &	Parameters ()
	Return a modifiable list of parameters that CLI knows about. More...

static std::string	ProgramName ()
	Get the program name as set by the PROGRAM_INFO() macro. More...

static void	RegisterProgramDoc (util::ProgramDoc *doc)
	Registers a ProgramDoc object, which contains documentation about the program. More...

static void	RestoreSettings (const std::string &name, const bool fatal=true)
	Restore all of the parameters and function mappings of the given name, if they exist. More...

static void	SetPassed (const std::string &name)
	Mark a particular parameter as passed. More...

static void	StoreSettings (const std::string &name)
	Take all parameters and function mappings and store them, under the given name. More...

Public Attributes
bool	didParse
	True, if CLI was used to parse command line options. More...

util::ProgramDoc *	doc
	Pointer to the ProgramDoc object. More...

FunctionMapType	functionMap

std::string	programName
	Holds the name of the program for –version. More...

Timers	timer
	Holds the timer objects. More...

Detailed Description

Parses the command line for parameters and holds user-specified parameters.

The CLI class is a subsystem by which parameters for machine learning methods can be specified and accessed. In conjunction with the macros PARAM_DOUBLE, PARAM_INT, PARAM_STRING, PARAM_FLAG, and others, this class aims to make user configurability of mlpack methods very easy. There are only three methods in CLI that a user should need: CLI::ParseCommandLine(), CLI::GetParam(), and CLI::HasParam() (in addition to the PARAM_*() macros).

Adding parameters to a program

$ ./executable --bar=5

Note: The = is optional; a space can also be used.

A parameter is specified by using one of the following macros (this is not a complete list; see core/io/cli.hpp):

PARAM_FLAG(ID, DESC, ALIAS)
PARAM_DOUBLE(ID, DESC, ALIAS, DEF)
PARAM_INT(ID, DESC, ALIAS, DEF)
PARAM_STRING(ID, DESC, ALIAS, DEF)

Parameters

ID	Name of the parameter.
DESC	Short description of the parameter (one/two sentences).
ALIAS	An alias for the parameter.
DEF	Default value of the parameter.

The flag (boolean) type automatically defaults to false; it is specified merely as a flag on the command line (no '=true' is required).

Here is an example of a few parameters being defined; this is for the KNN executable (methods/neighbor_search/knn_main.cpp):

PARAM_STRING_REQ("reference_file", "File containing the reference dataset.",
    "r");
PARAM_STRING_REQ("distances_file", "File to output distances into.", "d");
PARAM_STRING_REQ("neighbors_file", "File to output neighbors into.", "n");
PARAM_INT_REQ("k", "Number of furthest neighbors to find.", "k");
PARAM_STRING("query_file", "File containing query points (optional).", "q",
    "");
PARAM_INT("leaf_size", "Leaf size for tree building.", "l", 20);
PARAM_FLAG("naive", "If true, O(n^2) naive mode is used for computation.",
    "N");
PARAM_FLAG("single_mode", "If true, single-tree search is used (as opposed "
    "to dual-tree search.", "s");

More documentation is available on the PARAM_*() macros in the documentation for core/io/cli.hpp.

Documenting the program itself

In addition to allowing documentation for each individual parameter and module, the PROGRAM_INFO() macro provides support for documenting the program itself. There should only be one instance of the PROGRAM_INFO() macro. Below is an example:

PROGRAM_INFO("Maximum Variance Unfolding", "This program performs maximum "
   "variance unfolding on the given dataset, writing a lower-dimensional "
   "unfolded dataset to the given output file.");

This description should be verbose, and explain to a non-expert user what the program does and how to use it. If relevant, paper citations should be included.

Parsing the command line with CLI

To have CLI parse the command line at the beginning of code execution, only a call to ParseCommandLine() is necessary:

int main(int argc, char** argv)
{
  CLI::ParseCommandLine(argc, argv);
  ...
}

CLI provides –help and –info options which give nicely formatted documentation of each option; the documentation is generated from the DESC arguments in the PARAM_*() macros.

Getting parameters with CLI

When the parameters have been defined, the next important thing is how to access them. For this, the HasParam() and GetParam() methods are used. For instance, to see if the user passed the flag (boolean) "naive":

if (CLI::HasParam("naive"))
{
  Log::Info << "Naive has been passed!" << std::endl;
}

To get the value of a parameter, such as a string, use GetParam:

const std::string filename = CLI::GetParam<std::string>("filename");

Note: Options should only be defined in files which define main() (that is, main executables). If options are defined elsewhere, they may be spuriously included into other executables and confuse users. Similarly, if your executable has options which you did not define, it is probably because the option is defined somewhere else and included in your executable.

Bug:: The COUNTER variable is used in most cases to guarantee a unique global identifier for options declared using the PARAM_*() macros. However, not all compilers have this support–most notably, gcc < 4.3. In that case, the LINE macro is used as an attempt to get a unique global identifier, but collisions are still possible, and they produce bizarre error messages. See https://github.com/mlpack/mlpack/issues/100 for more information.

Definition at line 166 of file cli.hpp.

Member Typedef Documentation

◆ FunctionMapType

typedef std::map<std::string, std::map<std::string, void (*)(const util::ParamData&, const void*, void*)> > FunctionMapType

Map for functions and types.

Use as functionMap["typename"]["functionName"].

Definition at line 301 of file cli.hpp.

Member Function Documentation

◆ Add()

static void Add ( util::ParamData && d )

static

Adds a parameter to the hierarchy; use the PARAM_*() macros instead of this (i.e.

PARAM_INT()).

Parameters

d	Utility structure holding parameter data.

Referenced by CLIOption< N >::CLIOption(), GoOption< T >::GoOption(), JuliaOption< T >::JuliaOption(), MDOption< T >::MDOption(), PyOption< T >::PyOption(), and TestOption< N >::TestOption().

◆ Aliases()

static std::map<char, std::string>& Aliases ( )

static

Return a modifiable list of aliases that CLI knows about.

◆ ClearSettings()

static void ClearSettings ( )

static

Clear all of the settings, removing all parameters and function mappings.

Referenced by GoOption< T >::GoOption(), JuliaOption< T >::JuliaOption(), MDOption< T >::MDOption(), PyOption< T >::PyOption(), and TestOption< N >::TestOption().

◆ GetParam()

static T& GetParam ( const std::string & identifier )

static

Get the value of type T found while parsing.

You can set the value using this reference safely.

Parameters

identifier The name of the parameter in question.

◆ GetPrintableParam()

static std::string GetPrintableParam ( const std::string & identifier )

static

Cast the given parameter of the given type to a short, printable std::string, for use in status messages.

Ideally the message returned here should be only a handful of characters, and certainly no longer than one line.

Parameters

identifier The name of the parameter in question.

◆ GetRawParam()

static T& GetRawParam ( const std::string & identifier )

static

Get the raw value of the parameter before any processing that GetParam() might normally do.

So, e.g., for command-line programs, this does not perform any data loading or manipulation like GetParam() does. So if you want to access a matrix or model (or similar) parameter before it is loaded, this is the method to use.

Parameters

identifier The name of the parameter in question.

◆ GetSingleton()

static CLI& GetSingleton ( )

static

Retrieve the singleton.

As an end user, if you are just using the CLI object, you should not need to use this function—the other static functions should be sufficient.

In this case, the singleton is used to store data for the static methods, as there is no point in defining static methods only to have users call private instance methods.

Returns: The singleton instance for use in the static methods.

Referenced by CLIOption< N >::CLIOption(), mlpack::bindings::cli::EndProgram(), mlpack::util::GetParamWithInfo(), GoOption< T >::GoOption(), JuliaOption< T >::JuliaOption(), MDOption< T >::MDOption(), mlpack::bindings::cli::ParseCommandLine(), PyOption< T >::PyOption(), mlpack::util::ResetTimers(), and TestOption< N >::TestOption().

◆ HasParam()

static bool HasParam ( const std::string & identifier )

static

See if the specified flag was found while parsing.

Parameters

identifier The name of the parameter in question.

Referenced by mlpack::bindings::cli::EndProgram(), and mlpack::bindings::cli::ParseCommandLine().

◆ MakeInPlaceCopy()

static void MakeInPlaceCopy	(	const std::string &	outputParamName,
		const std::string &	inputParamName
	)

static

Given two (matrix) parameters, ensure that the first is an in-place copy of the second.

This will generally do nothing (as the bindings already do this automatically), except for command-line bindings, where we need to ensure that the output filename is the same as the input filename.

Parameters

outputParamName	Name of output (matrix) parameter.
inputParamName	Name of input (matrix) parameter.

◆ Parameters()

static std::map<std::string, util::ParamData>& Parameters ( )

static

Return a modifiable list of parameters that CLI knows about.

Referenced by CLIOption< N >::CLIOption(), mlpack::bindings::cli::EndProgram(), mlpack::bindings::cli::ParseCommandLine(), and mlpack::bindings::python::PrintOutputProcessing().

◆ ProgramName()

static std::string ProgramName ( )

static

Get the program name as set by the PROGRAM_INFO() macro.

Referenced by mlpack::bindings::cli::ParseCommandLine().

◆ RegisterProgramDoc()

static void RegisterProgramDoc ( util::ProgramDoc * doc )

static

Registers a ProgramDoc object, which contains documentation about the program.

If this method has been called before (that is, if two ProgramDocs are instantiated in the program), a fatal error will occur.

Parameters

doc	Pointer to the ProgramDoc object.

◆ RestoreSettings()

static void RestoreSettings	(	const std::string &	name,
		const bool	fatal = `true`
	)

static

Restore all of the parameters and function mappings of the given name, if they exist.

A std::invalid_argument exception will be thrown if fatal is true and no settings with the given name have been stored (with StoreSettings()).

Parameters

name	Name of settings to restore.
fatal	Whether to throw an exception on an unknown name.

Referenced by GoOption< T >::GoOption(), JuliaOption< T >::JuliaOption(), MDOption< T >::MDOption(), PyOption< T >::PyOption(), and TestOption< N >::TestOption().

◆ SetPassed()

static void SetPassed ( const std::string & name )

static

Mark a particular parameter as passed.

Parameters

name	Name of the parameter.

Referenced by mlpack::util::SetInputParam(), and TestOption< N >::TestOption().

◆ StoreSettings()

static void StoreSettings ( const std::string & name )

static

Take all parameters and function mappings and store them, under the given name.

This can later be restored with RestoreSettings(). If settings have already been saved under the given name, they will be overwritten. This also clears the current parameters and function map.

Parameters

name	Name of settings to save.

Referenced by GoOption< T >::GoOption(), JuliaOption< T >::JuliaOption(), MDOption< T >::MDOption(), PyOption< T >::PyOption(), and TestOption< N >::TestOption().

Member Data Documentation

◆ didParse

bool didParse

True, if CLI was used to parse command line options.

Definition at line 311 of file cli.hpp.

Referenced by mlpack::bindings::cli::ParseCommandLine().

◆ doc

util::ProgramDoc* doc

Pointer to the ProgramDoc object.

Definition at line 324 of file cli.hpp.

◆ functionMap

FunctionMapType functionMap

Definition at line 302 of file cli.hpp.

Referenced by CLIOption< N >::CLIOption(), mlpack::bindings::cli::EndProgram(), GoOption< T >::GoOption(), JuliaOption< T >::JuliaOption(), MDOption< T >::MDOption(), mlpack::bindings::cli::ParseCommandLine(), PyOption< T >::PyOption(), and TestOption< N >::TestOption().

◆ programName

std::string programName

Holds the name of the program for –version.

This is the true program name (argv[0]) not what is given in ProgramDoc.

Definition at line 315 of file cli.hpp.

◆ timer

Timers timer

Holds the timer objects.

Definition at line 318 of file cli.hpp.

Referenced by mlpack::bindings::cli::EndProgram(), mlpack::util::GetParamWithInfo(), and mlpack::util::ResetTimers().

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

/home/jenkins-mlpack/mlpack.org/_src/mlpack-3.3.2/src/mlpack/core/util/cli.hpp

Public Types

Static Public Member Functions

Public Attributes

Detailed Description

Adding parameters to a program

Documenting the program itself

Parsing the command line with CLI

Getting parameters with CLI

Member Typedef Documentation

◆ FunctionMapType

Member Function Documentation

◆ Add()

◆ Aliases()

◆ ClearSettings()

◆ GetParam()

◆ GetPrintableParam()

◆ GetRawParam()

◆ GetSingleton()

◆ HasParam()

◆ MakeInPlaceCopy()

◆ Parameters()

◆ ProgramName()

◆ RegisterProgramDoc()

◆ RestoreSettings()

◆ SetPassed()

◆ StoreSettings()

Member Data Documentation

◆ didParse

◆ doc

◆ functionMap

◆ programName

◆ timer