FileUtils Namespace Reference

Functions
TList *	findFilesInDirectory (const char *dirPath, const char *extension=0)
	Obtain list of file paths in directory (with given extension). More...
TFile *	openFile (const char *filePathName, Option_t *option="READ")
	Open ROOT file with given absolute path. More...
TTree *	getTree (TFile *file, const char *treeName)
	Parse absolute file path into path, name and extension. More...
TBranch *	getBranch (TTree *tree, const char *branchName)
	Safely get a branch from a ROOT tree. More...
Double_t	getBranchMinimum (TTree *tree, const char *branchName)
	Get minimum value in a tree branch. More...
Double_t	getBranchMaximum (TTree *tree, const char *branchName)
	Get maximum value in a tree branch. More...
Double_t	getBranchMinimumInFiles (TList *filePaths, const char *treeName, const char *branchName)
	Get minimum value in a tree branch across multiple files. More...
Double_t	getBranchMaximumInFiles (TList *filePaths, const char *treeName, const char *branchName)
	Get maximum value in a tree branch across multiple files. More...
TH1 *	getBranchHistogram (TTree *tree, const char *branchName, Int_t nBins=150)
	Shortcut to get a histogram from ROOT tree branch. More...
PathComponents	parseFilePath (const char *filePathName)
	Parse absolute file path into path, name and extension. More...
Int_t	exportValuesToGnuplot (const char *filename, std::vector< std::string > colNames, std::vector< double > values, const char *delimeter=" ")
	Append or save data to a Gnuplot file. More...
Int_t	exportCanvasToGnuplot (TCanvas *canvas, const char *delimeter=" ")
	Export ROOT canvas to ASCII file with data columns. More...

Detailed Description

Contains useful functions for ROOT file manipulation.

Function Documentation

exportCanvasToGnuplot()

Int_t FileUtils::exportCanvasToGnuplot	(	TCanvas *	canvas,
		const char *	delimeter = "   "
	)

Export ROOT canvas to ASCII file with data columns.

Function saves objects on Canvas - histograms, graph, function - to a text file ready to plot in Gnuplot.

Parameters

filename	absolute file path.
canvas	ROOT canvas to be saved.
delimeter	column delimeter (default " ").

Returns

0 if success, 1 if error.

exportValuesToGnuplot()

Int_t FileUtils::exportValuesToGnuplot	(	const char *	filename,
		std::vector< std::string >	colNames,
		std::vector< double >	values,
		const char *	delimeter = "   "
	)

Append or save data to a Gnuplot file.

Function creates a new or opens existing ASCII file. Next, it appends a line of values to the file.

Parameters

filename	absolute file path.
colNames	vector of strings with column names.
colNames	vector of doubles with row values.
delimeter	column delimeter (default " ").

Returns

0 if success, 1 if error.

findFilesInDirectory()

TList * FileUtils::findFilesInDirectory	(	const char *	dirPath,
		const char *	extension = 0
	)

Obtain list of file paths in directory (with given extension).

Function returns a TList* of TObjString* with full absolute paths of files in a given directory with given extension. Program exits if directory does not exist or not readable.

Parameters

dirPath	Directory path.
extension	Optional extension of files to find.

Returns

TList* of TObjString* with full absolute paths.

getBranch()

TBranch * FileUtils::getBranch	(	TTree *	tree,
		const char *	branchName
	)

Safely get a branch from a ROOT tree.

Function will stop program execution if the branch is not found.

Parameters

tree	pointer to the TTree.

Returns

branchName name of the branch to be found.

getBranchHistogram()

TH1 * FileUtils::getBranchHistogram	(	TTree *	tree,
		const char *	branchName,
		Int_t	nBins = 150
	)

Shortcut to get a histogram from ROOT tree branch.

Function automatically determines histogram minimum and maximum.

Parameters

tree	Pointer to the tree.
branchName	branchName name of a branch.
nBins	number of bins in the histogram. Default is 150.

Returns

TH1* pointer to the histogram.

getBranchMaximum()

Double_t FileUtils::getBranchMaximum	(	TTree *	tree,
		const char *	branchName
	)

Get maximum value in a tree branch.

Parameters

tree	pointer to the TTree.

Returns

branchName name of the branch.

getBranchMaximumInFiles()

Double_t FileUtils::getBranchMaximumInFiles	(	TList *	filePaths,
		const char *	treeName,
		const char *	branchName
	)

Get maximum value in a tree branch across multiple files.

Function is useful when simultaneously plotting a number of ROOT files with the same structure.

Parameters

filePaths	list of filepaths to be opened (TObjStrings*).
treeName	name of the tree in the ROOT file.

Returns

branchName name of the branch in the tree.

getBranchMinimum()

Double_t FileUtils::getBranchMinimum	(	TTree *	tree,
		const char *	branchName
	)

Get minimum value in a tree branch.

Parameters

tree	pointer to the TTree.

Returns

branchName name of the branch.

getBranchMinimumInFiles()

Double_t FileUtils::getBranchMinimumInFiles	(	TList *	filePaths,
		const char *	treeName,
		const char *	branchName
	)

Get minimum value in a tree branch across multiple files.

Function is useful when simultaneously plotting a number of ROOT files with the same structure.

Parameters

filePaths	list of filepaths to be opened (TObjStrings*).
treeName	name of the tree in the ROOT file.

Returns

branchName name of the branch in the tree.

getTree()

TTree * FileUtils::getTree	(	TFile *	file,
		const char *	treeName
	)

Parse absolute file path into path, name and extension.

Function parses file path into components: path, basename, name, extension.

Parameters

filePathName

absolute file path.

Returns

PathComponents struct with path components.

openFile()

TFile * FileUtils::openFile	(	const char *	filePathName,
		Option_t *	option = "READ"
	)

Open ROOT file with given absolute path.

Function checks if a file is good and returns a pointer to a ROOT file TFile* with given absolute path.

Parameters

filePathName	full ROOT file URI.
filePathName	ROOT option "NEW", "RECREATE", "UPDATE", "READ".. (optional, default is "READ").

Returns

Pointer to TFile* object.

parseFilePath()

PathComponents FileUtils::parseFilePath

(

const char *

filePathName

)

Parse absolute file path into path, name and extension.

Function parses file path into components: path, basename, name, extension.

Parameters

filePathName

absolute file path.

Returns

PathComponents struct with path components.