matrix multiplication in C++

Question

hi,

I have a number of 3x3 matricess that I want to multiply together For example:

m1*m2*m3*m4*m5

Although MTL is a recommended way, I don't have this library and can't use it.

Can someone please suggest a conventional way to multiply these 3x3 matrices (all matrices m1 to m5). Code snippet (for matrix multiplication and multiplying n matrices together) or pointer to some online code will be very useful

Answer 1

This site has code for multiplying two 3x3 matrices together: http://www.euclideanspace.com/maths/algebra/matrix/resources/code/index.htm#mul3.

Answer 2

Here is a package of very useful math routines including 3x3 matrix multiplication. The C++ template classes are implemented as header files that can be simply dropped into a project. The overloaded operators make code using this package look very clean. You can preview the implementation of the 3D vector template class online.

Here is a list of all the files in the archive, with those specific for 3x3 matrix multiplication highlighted in bold:

• Assert.c
• Assert.h
• intersect.cpp
• intersect.h
• line2.h
• Line3.h
• main.cpp
• Math.dsp
• Math.dsw
• Matrix2.h
• Matrix3.h
• matrix4.h
• MatrixN.h
• plane.h
• quaternion.h
• random.h
• Rect.h
• Spline.cpp
• Spline.h
• Utility.h
• vector2.h
• vector3.h
• vector4.h