Help needed please

asked 2015-09-11 07:19:45 -0600

Conor100 gravatar image

My actual measurement Yt is a [4x1] matrix but Ht is [1x4] and Xt is [ 4x1] so how can I get all of these to agree in the equation:

xt = xt + K(Yt - Ht.Xt)

Ideally I'd like

(Yt - Ht.Xt)

[4x1] - [4x1]

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Comments

transpose ?

LBerger gravatar imageLBerger ( 2015-09-11 07:41:58 -0600 )edit

Some remarks

  • Multiplying Ht and Xt works just fine. That is column and row multiplication. This will however yield a [4x4 matrix], not a [4x1] matrix as you are writing.
  • This will ensure that subtracting a [4x1] matrix with a [4x4] matrix will not work also due to dimensions not corresponding.
  • And thus all the following steps will fail also...
StevenPuttemans gravatar imageStevenPuttemans ( 2015-09-11 07:44:21 -0600 )edit

@StevenPuttemans yes I'm wrong ([1 row x 4columns] [4 rows x 1coloumn] =[1 row 1 column]Ht.Xt is a scalar so transpose scalar give a scalar).

@Conor100 your equation are not good

LBerger gravatar imageLBerger ( 2015-09-11 07:53:36 -0600 )edit

@LBerger, multiplying a 1x4 matrix with a 4x1 matrix is NOT a Scalar. This is the principle behind seperable filters, where you split up a 2D filter by a row and a column based filter. It will yield a 4x4 matrix...

StevenPuttemans gravatar imageStevenPuttemans ( 2015-09-11 07:59:22 -0600 )edit

@StevenPuttemans I just write ([1 row x 4columns] [4 rows x 1coloumn] =[1 row 1 column] Ht.Xt is a scalar is it wrong?

LBerger gravatar imageLBerger ( 2015-09-11 08:07:21 -0600 )edit

I am wondering if I could make Ht a [4x1] and Xt a [1x4] thus Ht.Xt would be a [4x4]. Can I now take the diagonals of this [4x4] to form a [4x1] to represent Ht.Xt and then proceed to calc Yt - Ht.Xt

Conor100 gravatar imageConor100 ( 2015-09-11 10:27:20 -0600 )edit
2

In my opinion, you should first check your formulas (the theory ?) and then implement it. Not trying to fix the formulas to make it works.

By the way, what is the name of the method you want to use (predictive control ?, ...) ?

Eduardo gravatar imageEduardo ( 2015-09-11 11:15:42 -0600 )edit
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