Package com.itextpdf.kernel.geom
Class Matrix
java.lang.Object
com.itextpdf.kernel.geom.Matrix
Keeps all the values of a 3 by 3 matrix and allows you to
do some math with matrices.
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Field Summary
FieldsModifier and TypeFieldDescriptionstatic final int
the row=1, col=1 position ('a') in the matrix.static final int
the row=1, col=2 position ('b') in the matrix.static final int
the row=1, col=3 position (always 0 for 2-D) in the matrix.static final int
the row=2, col=1 position ('c') in the matrix.static final int
the row=2, col=2 position ('d') in the matrix.static final int
the row=2, col=3 position (always 0 for 2-D) in the matrix.static final int
the row=3, col=1 ('e', or X translation) position in the matrix.static final int
the row=3, col=2 ('f', or Y translation) position in the matrix.static final int
the row=3, col=3 position (always 1 for 2-D) in the matrix.private final float[]
The values inside the matrix (the identity matrix by default). -
Constructor Summary
ConstructorsConstructorDescriptionMatrix()
constructs a new Matrix with identity.Matrix
(float tx, float ty) Constructs a matrix that represents translation.Matrix
(float a, float b, float c, float d, float e, float f) Creates a Matrix with 6 specified entries.Matrix
(float e11, float e12, float e13, float e21, float e22, float e23, float e31, float e32, float e33) Creates a Matrix with 9 specified entries. -
Method Summary
Modifier and TypeMethodDescriptionAdds a matrix from this matrix and returns the results.boolean
Checks equality of matrices.float
get
(int index) Gets a specific value inside the matrix.float
Computes the determinant of the matrix.int
hashCode()
Generates a hash code for this object.multiplies this matrix by 'b' and returns the result.Subtracts a matrix from this matrix and returns the results.toString()
Generates a String representation of the matrix.
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Field Details
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I11
public static final int I11the row=1, col=1 position ('a') in the matrix.- See Also:
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I12
public static final int I12the row=1, col=2 position ('b') in the matrix.- See Also:
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I13
public static final int I13the row=1, col=3 position (always 0 for 2-D) in the matrix.- See Also:
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I21
public static final int I21the row=2, col=1 position ('c') in the matrix.- See Also:
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I22
public static final int I22the row=2, col=2 position ('d') in the matrix.- See Also:
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I23
public static final int I23the row=2, col=3 position (always 0 for 2-D) in the matrix.- See Also:
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I31
public static final int I31the row=3, col=1 ('e', or X translation) position in the matrix.- See Also:
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I32
public static final int I32the row=3, col=2 ('f', or Y translation) position in the matrix.- See Also:
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I33
public static final int I33the row=3, col=3 position (always 1 for 2-D) in the matrix.- See Also:
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vals
private final float[] valsThe values inside the matrix (the identity matrix by default).For reference, the indeces are as follows:
I11 I12 I13
I21 I22 I23
I31 I32 I33
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Constructor Details
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Matrix
public Matrix()constructs a new Matrix with identity. -
Matrix
public Matrix(float tx, float ty) Constructs a matrix that represents translation.- Parameters:
tx
- x-axis translationty
- y-axis translation
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Matrix
public Matrix(float e11, float e12, float e13, float e21, float e22, float e23, float e31, float e32, float e33) Creates a Matrix with 9 specified entries.- Parameters:
e11
- element at position (1,1)e12
- element at position (1,2)e13
- element at position (1,3)e21
- element at position (2,1)e22
- element at position (2,2)e23
- element at position (2,3)e31
- element at position (3,1)e32
- element at position (3,2)e33
- element at position (3,3)
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Matrix
public Matrix(float a, float b, float c, float d, float e, float f) Creates a Matrix with 6 specified entries. The third column will always be [0 0 1] (row, column)- Parameters:
a
- element at (1,1)b
- element at (1,2)c
- element at (2,1)d
- element at (2,2)e
- element at (3,1)f
- element at (3,2)
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Method Details
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get
public float get(int index) Gets a specific value inside the matrix.For reference, the indeces are as follows:
I11 I12 I13
I21 I22 I23
I31 I32 I33- Parameters:
index
- an array index corresponding with a value inside the matrix- Returns:
- the value at that specific position.
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multiply
multiplies this matrix by 'b' and returns the result. See http://en.wikipedia.org/wiki/Matrix_multiplication- Parameters:
by
- The matrix to multiply by- Returns:
- the resulting matrix
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add
Adds a matrix from this matrix and returns the results.- Parameters:
arg
- the matrix to subtract from this matrix- Returns:
- a Matrix object
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subtract
Subtracts a matrix from this matrix and returns the results.- Parameters:
arg
- the matrix to subtract from this matrix- Returns:
- a Matrix object
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getDeterminant
public float getDeterminant()Computes the determinant of the matrix.- Returns:
- the determinant of the matrix
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equals
Checks equality of matrices. -
hashCode
public int hashCode()Generates a hash code for this object. -
toString
Generates a String representation of the matrix.
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