NMath User's Guide

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37.2 Creating Vector and Matrices from ADO.NET Objects (.NET, C#, CSharp, VB, Visual Basic, F#)

You can construct NMath vector and matrix classes from standard ADO.NET database objects. Real-value vector and matrix class constructors accept DataTable, DataRow, DataRowCollection, and DataView­­ objects, typically obtained from a database query. Complex number vector and matrix class constructors accept paired database objects containing the real and imaginary parts, respectively.

For example, assuming table is a DataTable instance:

Code Example – C#

var A = new DoubleMatrix( table );

Code Example – VB

Dim A As New DoubleMatrix(Table)

The resulting matrix has the same number of rows and columns as the data table. Note that all values must be able to be converted to a double through a cast. If not, the constructor throws an InvalidCastException.

Similarly, assuming view1 and view2 are DataView objects, this code creates a FloatComplexVector instance whose real parts are derived from the first column of view1, and whose imaginary parts are derived from the first column of view2:

Code Example – C#

var v = new FloatComplexVector( view1, view2 );

Code Example – VB

Dim V As New FloatComplexVector(View1, View2)

In this case, all values must be able to be converted to a float through a cast.


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