Class Util

java.lang.Object

org.jlab.detector.geant4.v2.SVT.Util

public class Util
extends Object

Geometry Utility

Universal class for a variety of useful methods.

• Vector manipulation: visualisation as volume, convert between Vector3D, Matrix and double[], convert difference to axis-angle rotation
• Volume manipulation: toString for GEMC, clone, append name, promote children, shift position, scale position
• Interfacing with Matrix to use appropriate rotation conversions for standard vectors and Geant
• File I/O

Version:

1.1.2

Author:

pdavies

Field Summary

Fields

Modifier and Type	Field	Description
static boolean	VERBOSE

Constructor Summary

Constructors

Constructor	Description
Util()

Method Summary

Modifier and Type	Method	Description
static void	appendChildrenName(Geant4Basic aVol, String aTag)	Recursively appends the given tag to the name of the descendents of the given volume.
static void	appendName(Geant4Basic aVol, String aTag)	Recursively appends the given tag to the name of the given volume and its descendents.
static double[]	calcDistance(Vector3d p0, Vector3d p1, double u0, double u1)	Calculates the distance with uncertainty between two measured points.
static void	closeOutputDataFile(String aName, Writer aFile)	Closes the given file.
static double[]	convertRotationVectorToGeant(double theta, double phi)	Converts the given spherical angles to Tait-Bryan angles suitable for Geant4Basic rotations.
static Matrix	convertRotationVectorToMatrix(double theta, double phi)	Converts the given spherical angles to a rotation matrix.
static double[]	convertVectorDiffToAxisAngle(Vector3d a, Vector3d b)	Calculates the difference between the two given direction vectors as an axis-angle rotation.
static Geant4Basic	createArrow(String aName, double aLen, double aCapRadius, double aPointerRadius, boolean aDisplayCapStart, boolean aDisplayPointer, boolean aDisplayCapEnd)	Creates a cylinder, capped with two spheres, pointing in the direction of the given vector.
static Geant4Basic	createArrow(String aName, Vector3d aVec, double aCapRadius, double aPointerRadius, boolean aDisplayCapStart, boolean aDisplayPointer, boolean aDisplayCapEnd)
static Geant4Basic	createArrow(String aName, Line3d aLine, double aCapRadius, double aPointerRadius, boolean aDisplayCapStart, boolean aDisplayPointer, boolean aDisplayCapEnd)
static String	gemcStringAll(Geant4Basic aVol)	Returns a string, in a format suitable for GEMC, of the given volume, including all children.
static double[][]	inputTaggedData(String aFilename, int recLen)	Reads data from a file of the format: String, double[].
static void	moveChildrenToMother(Geant4Basic aVol)	Replaces mother of children with mother of given volume, while preserving positions and rotations, and removes given volume from mother.
static Writer	openOutputDataFile(String aName)	Opens a file ready for writing.
static void	scalePosition(Geant4Basic aVol, double aFactor)	Recursively multiplies each position coordinate of the given volume and its children by the given scale factor.
static void	shiftPosition(Geant4Basic aVol, double aShiftX, double aShiftY, double aShiftZ)	Deprecated.
static int	subArraySum(int[] aArray, int aIndex)	Sums elements of aArray from 0 to (aIndex-1)
static double[]	toDoubleArray(Vector3d v)	Converts the given vector to a double[] array.
static Matrix	toMatrix(Vector3d v)	Converts the given vector to a column-based Matrix.
static Vector3d	toVector3d(double[] a)	Converts the given double[] array to a vector.
static Vector3d	toVector3d(Matrix m)	Converts the given column-based Matrix to a vector.
static Vector3d	toVector3D(double[] a)	Converts the given double[] array to a vector.
static void	writeLine(Writer aWriter, String aLine)	Appends the given String to the given file.

Methods inherited from class java.lang.Object

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

Field Details

VERBOSE

public static boolean VERBOSE

Constructor Details

Util

public Util()

Method Details

calcDistance

public static double[] calcDistance(Vector3d p0,
 Vector3d p1,
 double u0,
 double u1)

Calculates the distance with uncertainty between two measured points.

Parameters:

p0 - first point

p1 - second point

u0 - uncertainty in the measurement of the coordinates of the first point

u1 - uncertainty in the measurement of the coordinates of the second point

Returns:

double[] an array containing a {value,uncertainty} pair

moveChildrenToMother

public static void moveChildrenToMother(Geant4Basic aVol)

Replaces mother of children with mother of given volume, while preserving positions and rotations, and removes given volume from mother. Effectively promotes a given volume's children to the same rank as that volume in the tree hierarchy.

Parameters:

aVol - volume whose children are to be moved

appendName

public static void appendName(Geant4Basic aVol,
 String aTag)

Recursively appends the given tag to the name of the given volume and its descendents.

Parameters:

aVol - volume

aTag - string to append

appendChildrenName

public static void appendChildrenName(Geant4Basic aVol,
 String aTag)

Recursively appends the given tag to the name of the descendents of the given volume.

Parameters:

aVol - volume

aTag - string to append

gemcStringAll

public static String gemcStringAll(Geant4Basic aVol)

Returns a string, in a format suitable for GEMC, of the given volume, including all children.

Parameters:

aVol - volume

Returns:

String multiple lines of text

toMatrix

public static Matrix toMatrix(Vector3d v)

Converts the given vector to a column-based Matrix.

Parameters:

v - vector

Returns:

Matrix column-based Matrix

toVector3d

public static Vector3d toVector3d(Matrix m)
                           throws IllegalArgumentException

Converts the given column-based Matrix to a vector.

Parameters:

m - matrix

Returns:

Vector3D vector

Throws:

IllegalArgumentException - matrix wrong size

toDoubleArray

public static double[] toDoubleArray(Vector3d v)

Converts the given vector to a double[] array.

Parameters:

v - vector

Returns:

double[] array

toVector3D

public static Vector3d toVector3D(double[] a)
                           throws IllegalArgumentException

Converts the given double[] array to a vector.

Parameters:

a - array

Returns:

Vector3D vector

Throws:

IllegalArgumentException - array wrong size

toVector3d

public static Vector3d toVector3d(double[] a)
                           throws IllegalArgumentException

Converts the given double[] array to a vector.

Parameters:

a - array

Returns:

Vector3d vector

Throws:

IllegalArgumentException - array wrong size

createArrow

public static Geant4Basic createArrow(String aName,
 Vector3d aVec,
 double aCapRadius,
 double aPointerRadius,
 boolean aDisplayCapStart,
 boolean aDisplayPointer,
 boolean aDisplayCapEnd)

createArrow

public static Geant4Basic createArrow(String aName,
 Line3d aLine,
 double aCapRadius,
 double aPointerRadius,
 boolean aDisplayCapStart,
 boolean aDisplayPointer,
 boolean aDisplayCapEnd)

createArrow

public static Geant4Basic createArrow(String aName,
 double aLen,
 double aCapRadius,
 double aPointerRadius,
 boolean aDisplayCapStart,
 boolean aDisplayPointer,
 boolean aDisplayCapEnd)

Creates a cylinder, capped with two spheres, pointing in the direction of the given vector. Length of cylinder is equal to magnitude of vector.

Parameters:

aName - subvolumes will have _arrow# appended to aName

aLen - length of FIXME

aCapRadius - radius of spherical caps

aPointerRadius - radius of cylindrical shaft

aDisplayCapStart - switch to show start cap

aDisplayPointer - switch to show shaft

aDisplayCapEnd - switch to show end cap

Returns:

Geant4Basic pseudo volume containing arrow components

convertRotationVectorToMatrix

public static Matrix convertRotationVectorToMatrix(double theta,
 double phi)

Converts the given spherical angles to a rotation matrix. Tait-Bryan/Euler Intrinsic ZYX/Extrinsic XYZ.

Parameters:

theta - elevation angle in radians

phi - azimuth angle in radians

Returns:

Matrix a column-based rotation matrix

convertRotationVectorToGeant

public static double[] convertRotationVectorToGeant(double theta,
 double phi)

Converts the given spherical angles to Tait-Bryan angles suitable for Geant4Basic rotations. Tait-Bryan/Euler Intrinsic XYZ/Extrinsic ZYX. N.B. Geant = passive/alias, Java = active/alibi, so please negate the angles before passing to Geant4Basic.

Parameters:

theta - elevation angle in radians

phi - azimuth angle in radians

Returns:

double[] xyz angles in radians

convertVectorDiffToAxisAngle

public static double[] convertVectorDiffToAxisAngle(Vector3d a,
 Vector3d b)

Calculates the difference between the two given direction vectors as an axis-angle rotation. http://math.stackexchange.com/questions/293116/rotating-one-3d-vector-to-another

Parameters:

a - vector

b - vector

Returns:

double[] axis-angle rotation, format: { rx, ry, rz, ra }, angle in radians

scalePosition

public static void scalePosition(Geant4Basic aVol,
 double aFactor)

Recursively multiplies each position coordinate of the given volume and its children by the given scale factor.

Parameters:

aVol - volume

aFactor - scale factor

shiftPosition

public static void shiftPosition(Geant4Basic aVol,
 double aShiftX,
 double aShiftY,
 double aShiftZ)

Deprecated.

Translates the given volume's position by the given shifts.

Parameters:

aVol - volume

aShiftX - shift

aShiftY - shift

aShiftZ - shift

subArraySum

public static int subArraySum(int[] aArray,
 int aIndex)

Sums elements of aArray from 0 to (aIndex-1)

Parameters:

aArray - an array of ints

aIndex - a terminating index

Returns:

int cumulative sum of elements

inputTaggedData

public static double[][] inputTaggedData(String aFilename,
 int recLen)
                                  throws IllegalArgumentException,
IOException

Reads data from a file of the format: String, double[].

Parameters:

aFilename - name of file

recLen - number of fields to read per record

Returns:

double[][] array indexed as [record][field]

Throws:

IllegalArgumentException - null or empty filename

IOException - incorrect record length

openOutputDataFile

public static Writer openOutputDataFile(String aName)
                                 throws IllegalArgumentException

Opens a file ready for writing. Terminates program if IOException occurs.

Parameters:

aName - a file name

Returns:

Writer a file handle

Throws:

IllegalArgumentException - null or empty filename

writeLine

public static void writeLine(Writer aWriter,
 String aLine)

Appends the given String to the given file. Terminates program if IOException occurs.

Parameters:

aWriter - file handle

aLine - string to write

closeOutputDataFile

public static void closeOutputDataFile(String aName,
 Writer aFile)

Closes the given file. Terminates program if IOException occurs.

Parameters:

aName - file name

aFile - file handle