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switch the matrix type built by factory methods depending on the dimension 

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@783680 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Luc Maisonobe 2009-06-11 08:06:05 +00:00
parent 37ee8dbfe6
commit 6fb3ae713e
1 changed files with 33 additions and 10 deletions
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43
src/java/org/apache/commons/math/linear/MatrixUtils.java
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@ -46,6 +46,11 @@ public class MatrixUtils {
/**
* Returns a {@link RealMatrix} with specified dimensions.
* <p>The type of matrix returned depends on the dimension. Below
* 2<sup>12</sup> elements (i.e. 4096 elements or 64&times;64 for a
* square matrix) which can be stored in a 32kB array, a {@link
* RealMatrixImpl} instance is built. Above this threshold a {@link
* BlockRealMatrix} instance is built.</p>
* <p>The matrix elements are all set to 0.0.</p>
* @param rows number of rows of the matrix
* @param columns number of columns of the matrix
@ -53,11 +58,16 @@ public class MatrixUtils {
* @see #createRealMatrix(double[][])
*/
public static RealMatrix createRealMatrix(final int rows, final int columns) {
return new DenseRealMatrix(rows, columns);
return (rows * columns <= 4096) ?
new RealMatrixImpl(rows, columns) : new BlockRealMatrix(rows, columns);
}
/**
* Returns a {@link FieldMatrix} with specified dimensions.
* <p>The type of matrix returned depends on the dimension. Below
* 2<sup>12</sup> elements (i.e. 4096 elements or 64&times;64 for a
* square matrix), a {@link FieldMatrix} instance is built. Above
* this threshold a {@link BlockFieldMatrix} instance is built.</p>
* <p>The matrix elements are all set to field.getZero().</p>
* @param <T> the type of the field elements
* @param field field to which the matrix elements belong
@ -70,41 +80,54 @@ public class MatrixUtils {
public static <T extends FieldElement<T>> FieldMatrix<T> createFieldMatrix(final Field<T> field,
final int rows,
final int columns) {
return new DenseFieldMatrix<T>(field, rows, columns);
return (rows * columns <= 4096) ?
new FieldMatrixImpl<T>(field, rows, columns) : new BlockFieldMatrix<T>(field, rows, columns);
}
/**
* Returns a {@link RealMatrix} whose entries are the the values in the
* the input array. The input array is copied, not referenced.
* the input array.
* <p>The type of matrix returned depends on the dimension. Below
* 2<sup>12</sup> elements (i.e. 4096 elements or 64&times;64 for a
* square matrix) which can be stored in a 32kB array, a {@link
* RealMatrixImpl} instance is built. Above this threshold a {@link
* BlockRealMatrix} instance is built.</p>
* <p>The input array is copied, not referenced.</p>
*
* @param data input array
* @return RealMatrix containing the values of the array
* @throws IllegalArgumentException if <code>data</code> is not rectangular
* (not all rows have the same length) or empty
* @throws NullPointerException if <code>data</code> is null
* @throws NullPointerException if either <code>data</code> or
* <code>data[0]</code> is null
* @see #createRealMatrix(int, int)
*/
public static RealMatrix createRealMatrix(double[][] data) {
return new DenseRealMatrix(data);
return (data.length * data[0].length <= 4096) ?
new RealMatrixImpl(data) : new BlockRealMatrix(data);
}
/**
* Returns a {@link FieldMatrix} whose entries are the the values in the
* the input array.
* <p>
* The input array is copied, not referenced.
* </p>
* <p>The type of matrix returned depends on the dimension. Below
* 2<sup>12</sup> elements (i.e. 4096 elements or 64&times;64 for a
* square matrix), a {@link FieldMatrix} instance is built. Above
* this threshold a {@link BlockFieldMatrix} instance is built.</p>
* <p>The input array is copied, not referenced.</p>
* @param <T> the type of the field elements
* @param data input array
* @return RealMatrix containing the values of the array
* @throws IllegalArgumentException if <code>data</code> is not rectangular
* (not all rows have the same length) or empty
* @throws NullPointerException if <code>data</code> is null
* @throws NullPointerException if either <code>data</code> or
* <code>data[0]</code> is null
* @see #createFieldMatrix(Field, int, int)
* @since 2.0
*/
public static <T extends FieldElement<T>> FieldMatrix<T> createFieldMatrix(T[][] data) {
return new DenseFieldMatrix<T>(data);
return (data.length * data[0].length <= 4096) ?
new FieldMatrixImpl<T>(data) : new BlockFieldMatrix<T>(data);
}
/**