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POLinear Algebra MatrixMultiply method
 

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    <p><b>EDIT:</b><br> After fixing the syntax error and working with this algorithm I found the MKL provider is not the matrix multiplication needed. This algorithm simply multiplies element by element and does not compute the <code>dot(row_n,column_n)</code> as I had originally thought. </p> <p><a href="http://numerics.mathdotnet.com/api/MathNet.Numerics.LinearAlgebra.Single/DenseMatrix.htm#Multiply" rel="nofollow">other source</a></p> <p><b>End Edit</b></p> <p>I can't get this passed the compiler. I have looked all over for a good example but have come up short. The documentation I'm referencing is <a href="http://numerics.mathdotnet.com/api/MathNet.Numerics.Algorithms.LinearAlgebra.Mkl/MklLinearAlgebraProvider.htm#MatrixMultiply" rel="nofollow">MklLinearAlgebraProvider</a></p> <p><code>MathNet.Numerics.Algorithms.LinearAlgebra.Mkl.MklLinearAlgebraProvider</code> </p> <p>I'm trying to write a simple method to compute the rotation matrix <code>R = rz*ry*rx</code> from Euler angles. The problem is the compiler won't take <code>ryXrx</code> or <code>resultMat</code> arrays I'm trying to pass it. I've tried <code>out</code> keyword as well.</p> <p><code>inputMat</code> is a 1-D array of the form {x,y,z,rx,ry,rz} where x,y and z are translations and rx,ry and rz are rotation angles in degrees.</p> <pre><code> private float[,] EulerToHMat(float[] inputMat) { var linalg = new MathNet.Numerics.Algorithms.LinearAlgebra.Mkl.MklLinearAlgebraProvider(); double rzRad = ((double)inputMat[5])*Math.PI/180; double cosZ = Math.Cos(rzRad); double sinZ = Math.Sin(rzRad); double ryRad = ((double)inputMat[4])*Math.PI/180; double cosY= Math.Cos(ryRad); double sinY = Math.Sin(ryRad); double rxRad = ((double)inputMat[3])*Math.PI/180; double cosX= Math.Cos(rxRad); double sinX = Math.Sin(rxRad); var rz = new float[,] { { (float)cosZ, -(float)sinZ, 0 }, { (float)sinZ, (float)cosZ , 0 }, {0,0,1 } }; var ry = new float[,] { { (float)cosY , 0 , (float)sinY }, { 0, 1 , 0 }, { -(float)sinY, 0, (float)cosY } }; var rx = new float[,] { {1,0,0 }, {0,(float)cosX,-(float)sinX }, {0,(float)sinX,(float)cosX } }; var ryXrx = new float[3,3]; var resultMat = new float[3, 3]; // won't take the matrix --ryXrx-- here linalg.MatrixMultiply(ry, 3, 3, rx, 3, 3,ryXrx); // won't take the matrix --resultMat-- here linalg.MatrixMultiply(rz, 3, 3, ryXrx, 3, 3,resultMat); return resultMat; } </code></pre> <p>This seems like it should be simple.... Please ignore the casting mess.</p>
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    1. COWhy don't you read the documentation you've linked yourself to? These functions clearly don't accept `float[3,3]` type arguments.
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