Tranforming a matrix

Answer Matrix D:
[-1.40787]
[1.49657 ]
[-3.12701]
[1.000000]

Transforming the matrix D with T
Translation Matrix T:
[ 1.0...0.00...0.00...4.0]
[0.00...1.0....0.00...5.0]
[0.00...0.00...1.0....2.0]
[0.00...0.00...0.00...1.0]
Matrix Multiply TxD:
[( 1.0*-1.4 )+( 0.00*1.5 )+( 0.00*-3.1 )+( 4.0*1.0 )
[( 0.00*-1.4 )+( 1.0*1.5 )+( 0.00*-3.1 )+( 5.0*1.0 )]
[( 0.00*-1.4 )+( 0.00*1.5 )+( 1.0*-3.1 )+( 2.0*1.0 )]
[( 0.00*-1.4 )+( 0.00*1.5 )+( 0.00*-3.1 )+( 1.0*1.0 )]
Answer : (new location of point)
[2.59213]
[6.49657]
[-1.12701]
[1.00000]

Does this look right?

Hi

I get the same result, so your calculation seems to be correct. I assume that you are using 4.0, 5.0, 2.0 as your displacement vector in the translation.

If we use the same values for the sake of computation, then for scaling we would get:

[-1.40787]
[1.49657 ]
[-3.12701]
[1.000000]

Scaling Matrix S

[4.0...0.00...0.00...0.0]
[0.00...5.0....0.00...0.0]
[0.00...0.00...2.0....0.0]
[0.00...0.00...0.00..1.0]

and then

[-5.63148]
[7.48285]
[-6.25402]
[1.00000]


Do you agree?

Yes I get the same answer

[-5.63148]
[7.48285]
[-6.25402]
[1.00000]

but

This is assuming we are using the 3 dimensional homogenous point (4.0, 5.0, 2.0, 1) on the coordinates basis vectors (1,0,0) , (0,1,0) and (0,0,1)

Im not following you here!