```Date: Thu, 20 Jan 2005 11:29:21 -0300 Reply-To: Hector Maletta Sender: "SPSSX(r) Discussion" From: Hector Maletta Subject: Re: Vector multiplication: a clarification Comments: To: "Peck, Jon" In-Reply-To: <5CFEFDB5226CB54CBB4328B9563A12EEDB5EAB@hqemail2.spss.com> Content-Type: text/plain; charset="US-ASCII" Jon, Thanks for the tips. In my case I would do a vectorial multiplication of one vector of variables for another vector of variables, FOR EACH CASE. It is essentially a COMPUTE transformation, namely the sum of a series of products. Therefore I imagine the size of the dataset (i.e. the number of cases) is not necessarily an issue. Can I do what I want without using a LOOP structure, just multiplying the two vectors of variables, say X and W, to obtain a third set of variables, say Z? What I imagine is something like this: VECTOR Z = Z1 TO Z50. VECTOR X = X1 TO X50. VECTOR W = W1 TO W50. COMPUTE Z = X * W. Hector > -----Original Message----- > From: SPSSX(r) Discussion [mailto:SPSSX-L@LISTSERV.UGA.EDU] > On Behalf Of Peck, Jon > Sent: Thursday, January 20, 2005 11:18 AM > To: SPSSX-L@LISTSERV.UGA.EDU > Subject: Re: Vector multiplication: a clarification > > > The matrix language contains all the usual matrix operations > as well as elementwise operators and many more complex > functions such as Cholesky decomposition, determinants, > eigenvalues/vectors, and SVD, just to name a few. And it has > programming structures such as loops. > > You should be aware, though, that Matrix, unlike most SPSS > procedures keeps its data in memory, so very large datasets > will require lots of memory (or big swap files and patience). > But lots of memory is pretty common these days. > > Regards, > Jon Peck > > -----Original Message----- > From: SPSSX(r) Discussion [mailto:SPSSX-L@LISTSERV.UGA.EDU] > On Behalf Of Mark A Davenport MADAVENP > Sent: Thursday, January 20, 2005 7:36 AM > To: SPSSX-L@LISTSERV.UGA.EDU > Subject: Re: [SPSSX-L] Vector multiplication: a clarification > > Oops, I should read messages more closely. It does appear > that SPSS matrix notation will handle vectors and scalars. I > have only used it once with 2 matrices. SPSSX-L@VM.MARIST.EDU cc > > Subject > Re: Vector multiplication > > > > > > > About my question on multiplying two vectors of variables, > Richard Ristow > wrote: > > Unless I'm much mistaken, there's no way to manipulate a > vector as a > > unit. > > I supposed the matrix language available in SPSS, which I am > not very much acquainted with, may have some way of doing > vector and matrix algebra operations, such as vector > multiplication. It does apparently not. Am I wrong? > > Hector > ```

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