[Groovy] Class Matrix

java.lang.Object
  Expando
      Matrix

All Implemented Interfaces:

java.lang.Iterable

class Matrix
extends Expando

Wraps an Apache-Commons-Math matrix of double values with a Groovy interface for convenient access. Because it wraps the underlying matrix as a delegate, all the original methods of the Commons-Math implementation are available directly, along with Groovy-enhanced versions.

The most basic enhancements come in the form of random access operators that allowthe Matrix class to be referenced using square-bracket notation:

 Matrix m = new Matrix(2,2,[1,2,3,4])
 assert m[0][0] == 2
 assert m[1][1] == 4
 

 assert m[0] == [1,2]
 assert m[1] == [3,4]
 

 assert m[][0] == [1,3]
 assert m[][1] == [2,4]
 

 assert m[0].collect { it.any { it > 2 }  } == [ false, true ]
 assert m[][0].collect { it > 1 } == [ false, true ]
 

Transforming the whole matrix can be done using transform:

 assert m.transform { it * 2 } == Matrix(2,2,[2,4,6,8])
 

 assert m.transform { value, row, column -> value * 2 } == Matrix(2,2,[2,4,6,8])
 

Authors:

simon.sadedin@mcri.edu.au

DISPLAY_ROWS

static final int DISPLAY_ROWS

How many rows are displayed in toString() and other calls that format output

matrix

@Delegate
Array2DRowRealMatrix matrix

names

java.util.List names

Matrix

Matrix(int rows, int columns)

Matrix

Matrix(MatrixColumn... sourceColumns)

Matrix

Matrix(java.lang.Iterable rows)

Matrix

Matrix(double values)

Matrix

Matrix(int rows, int columns, java.util.List data)

Matrix

Matrix(int rows, int columns, double[] matrixData)

Matrix

Matrix(Array2DRowRealMatrix m)

col

@CompileStatic
MatrixColumn col(int n)

collect

@CompileStatic
java.lang.Object collect(groovy.lang.Closure c)

Specialization of collect: if 1 arg then just pass the row, if 2 args, pass the row AND the index.

Parameters:

c Closure - to execute for each row in the matrix

Returns:

results collected

divide

Matrix divide(double d)

eachRow

@CompileStatic
void eachRow(groovy.lang.Closure c)

findIndexValues

@CompileStatic
java.util.List findIndexValues(groovy.lang.Closure c)

getAt

@CompileStatic
java.lang.Object getAt(java.lang.Object n)

Implementation of the [] operator. Adds several different behaviors:

• Plain old indexing returns a row: m[4] returns 5th row of matrix.
• Double indexing returns a cell: m[4][5] returns 6th column of 4th row.
• Empty index returns a column: m[][6] returns 7th column
• List (or any iterable) index returns rows matching indices:

 Matrix m = new Matrix([1..80], 10, 8)
 m[2..4] == [ [ 9..16 ], [17..24], [25..32] ] 
Parameters:
n
Returns:

        

getColumns

java.util.List getColumns(java.util.List names)

getColumns

java.util.List getColumns()

grep

@CompileStatic
Matrix grep(groovy.lang.Closure c)

Filter the rows of this matrix and return a Matrix as a result

Parameters:

c - a Closure to evaluate

Returns:

Matrix for which the closure c returns a non-false value

initFromList

@CompileStatic
void initFromList(int rows, int columns, java.util.List data)

iterator

@CompileStatic
java.util.Iterator iterator()

load

static Matrix load(java.lang.String fileName)

minus

Matrix minus(Matrix m)

minus

Matrix minus(double x)

multiply

Matrix multiply(double d)

multiply

Matrix multiply(Matrix m)

plus

Matrix plus(Matrix m)

plus

Matrix plus(double x)

putAt

@CompileStatic
void putAt(int n, java.lang.Object values)

row

@CompileStatic
double[] row(int n)

save

void save(java.lang.String fileName)

save

void save(Writer w)

setColumnNames

void setColumnNames(java.util.List names)

setNames

void setNames(java.util.List names)

subsetRows

@CompileStatic
double subsetRows(java.lang.Iterable i)

Return a subset of the rows indicated by the indices in the given iterable (Note that the indices don't need to be consecutive or monotonic).

Parameters:

i

Returns:

toString

java.lang.String toString()

transform

@CompileStatic
Matrix transform(groovy.lang.Closure c)

Transforms a matrix by processing each element through the given closure. The closure must take either one argument or three arguments. The one argument version is only passed data values, while the three argument version is passed the data value and also the row and column position.

Parameters:

c - A closure taking 1 or 3 arguments (data value, or data value, row, column)

Returns:

A matrix reflecting the transformed data values

transformRows

@CompileStatic
Matrix transformRows(groovy.lang.Closure c)

Transform the given matrix by passing each row to the given closure. If the closure accepts two arguments then the row index is passed as well. The closure must return a double array to replace the array passed in. If null is returned then the data is left unchanged.

Parameters:

c - Closure to process the data with.

Returns:

transformed Matrix

transpose

Matrix transpose()

which

java.util.List which(groovy.lang.Closure c)

Shorthand to give a familiar function to R users

Groovy Documentation