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Date: Tue, 31 Jan 2012 07:53:09 -0800 (PST)
From: Pedro Giffuni <pfg@apache.org>
Reply-To: pfg@apache.org
Subject: Re: [code] 4.x Feature planning: MTL proposal
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--- Mar 31/1/12, Rob Weir <robweir@apache.org> ha scritto:=0A=0A> =0A> How =
would this be exposed in Calc?=A0 Are you thinking of=0A> having it handle =
the matrix spreadsheet functions like=0A> MMULT() and MINVERSE()?=0A=0AYes =
at first it would replace the existing matrix=0Aoperations. In a spreadshee=
t everything is composed=0Aof matrices so even managing the existing calcul=
ations=0Awith MTL would bring some level of simplification and=0Acode reduc=
tion=0A=0A> Or were you thinking of exposing some more advanced=0A> functio=
ns or tools, like eigenvectors/eigenvalues=0A> calculations?=0A>=0A=0AThat =
would be a latter step: arguably this would be=0Aof great use for a small g=
roup of people. An accountant,=0Afor example, will have no use for it.=0A =
=0A> It would be good to understand the advantages of changes=0A> the code =
here.=A0 I assume it would be for better performance=0A> with large spreads=
heets, especially now that OOo supports=0A> 1 million rows of data.=0A> =0A=
=0ANormally, doing code that scales well with massive amount=0Aof data actu=
ally slows down small size calculations but=0Asmall size calculations are a=
lready so fast to compute that=0Ano one will notice. The difference will be=
 in big problems,=0Alet's say we save an half an hour in a calculation that=
 takes=0A28 hours.=0A=0ASuch calculations can be very common in scientific=
=0Aenvironments and in niche markets like the oil industry:=0Athere, people=
 have specialized software that they just fork=0Aand forget about. The adva=
ntage of Calc is the interface,=0Aand while people don't appreciate having =
a spreadsheet open=0Afor 28 hours, no matter the size, this will be very us=
eful=0Afor medium sized calculations and maybe to interface with=0Aspeciali=
zed modules (volunteer can look at MUMPS).=0A=0ATo make some idea, I think =
this would compete to some extent=0Awith Matlab-like toolsets, where people=
 have a general matrix=0Asolving environment and additional toolsets availa=
ble for=0Aspecialized problems.=0A=0APedro.