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[WP 34s] Matrix multiplication procedure - Printable Version

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[WP 34s] Matrix multiplication procedure - Marcio - 06-22-2015 10:32 PM

Hello all,

Would you be kind enough as to explain with an example how to do matrix multiplication in the 34s? So far I have only been able to invert them, mostly because all it takes is store the data in \(R_n\) and then call \(M^{-1}\) with the descriptor in \(x\). Quite easy.

As to multiply matrices, the manual says the descriptors should be in \(z\) and \(y\), the problem however is that I don't quite understand what should be in \(x\).

Very much appreciated.

Marcio


RE: [WP 34s] Matrix multiplication procedure - Thomas Klemm - 06-22-2015 11:30 PM

WP 34S pocket reference

M×                z y x → r
Take two matrix descriptors y and z, and the
integer part of x as the base address of the re-
sult. Returns (Z)·(Y)=(X). All calculations are
done in internal high precision (39 digits).
The fractional part of x is updated to match
the resulting matrix - no overlap checking is
performed.

(06-22-2015 10:32 PM)Marcio Wrote:  the problem however is that I don't quite understand what should be in \(x\).

That is the matrix-descriptor of the result. Make sure it doesn't overlap with z and y.

HTH
Thomas


RE: [WP 34s] Matrix multiplication procedure - Marcio - 06-22-2015 11:38 PM

(06-22-2015 11:30 PM)Thomas Klemm Wrote:  
(06-22-2015 10:32 PM)Marcio Wrote:  the problem however is that I don't quite understand what should be in \(x\).

That is the matrix-descriptor of the result. Make sure it doesn't overlap with z and y.

HTH
Thomas

Quite obvious after this little hint.