Excel to Linux DDE solution?

I'm looking for a simple, ideally open source solution, that will enable
me to invoke UNIX/LINUX commands from within Excel/VB and exchange data
between excel and Linux.

Any help much appreciated.

Kiwi Trader Guy wrote:
> I'm looking for a simple, ideally open source solution, that will
enable
> me to invoke UNIX/LINUX commands from within Excel/VB and exchange
data
> between excel and Linux.

After reading some of your other posts, I'm wondering what it is you
are needing that requires such a Windows-to-Linux IPC runtime
interface. Perhaps, if you related your objectives (not your notion of
the solution just yet) we might be able to point you in the right
direction.

As for your immediate question I would say give up the quest of trying
to run concurrent OSes (one "real", one "virtual") and pass _any_
commands from one to the other where Excel is involved -- it passes
data (arguments) in a "unique" fashion that makes communicating with it
from _within_ Windows a minefield.

And except for database access, I'm not aware of any (non-MS, standards
based) network protocols that Excel hooks into. I'm not up-to-snuff on
current Excel network capabilities, however. Can MS's RPC mechanism
work with Linux. Big doubts...

I'm guessing you've found an Excel solution for your "math"
requirements? If you can share what it is, we may be able to point in
the direction of something that is comparable/interoperable (even
better?

At any rate, you may want to look at these:
http://www.gnome.org/projects/gnumeric/features.shtml
http://www.gnome.org/projects/gnumeric/functions.shtml
http://www.r-project.org/

needing more info,
prg

On Fri, 25 Mar 2005 20:44:28 +1200, Kiwi Trader Guy wrote:

> I'm looking for a simple, ideally open source solution, that will enable
> me to invoke UNIX/LINUX commands from within Excel/VB and exchange data
> between excel and Linux.
>
> Any help much appreciated.

1) Write a Windows client i.e. a library, dll, .NET component, whatever
you're most comfortable with.

2) Write a server to run on the Unix/Linux system. Language of your choice.

3) The client and server communicate via tcp-ip. The Excel/VB app sends
commands to the client, the client forwards them to the server, the server
forks a process on the Unix/Linux box and executes the command.

> 1) Write a Windows client i.e. a library, dll, .NET component, whatever
> you're most comfortable with.
>
> 2) Write a server to run on the Unix/Linux system. Language of your choice.
>
> 3) The client and server communicate via tcp-ip. The Excel/VB app sends
> commands to the client, the client forwards them to the server, the server
> forks a process on the Unix/Linux box and executes the command.

Thanks,

This is the way to do it yes. I've noticed a Shell command from within Excel
so could use Windows SSH. Plus I could use a Linux based Database with
triggers invoked using ADO I guess. My trading systems are based around
Linux, but I was looking to offload some processing and crunch some numbers on
the server.

Would be nice if there was a set of libraries to assist with this.

Kiwi Trader Guy wrote:
> > 1) Write a Windows client i.e. a library, dll, .NET component,
whatever
> > you're most comfortable with.
> >
> > 2) Write a server to run on the Unix/Linux system. Language of your
choice.
> >
> > 3) The client and server communicate via tcp-ip. The Excel/VB app
sends
> > commands to the client, the client forwards them to the server, the
server
> > forks a process on the Unix/Linux box and executes the command.
>
> Thanks,
>
> This is the way to do it yes. I've noticed a Shell command from
within Excel
> so could use Windows SSH. Plus I could use a Linux based Database
with
> triggers invoked using ADO I guess. My trading systems are based
around
> Linux, but I was looking to offload some processing and crunch some
numbers on
> the server.
>
> Would be nice if there was a set of libraries to assist with this.

Now you're clarifying ... a bit ... ;-)

Is this along the lines of what you're seeking?

You want a database on one machine -- perhaps Linux.

You have Excel running on Windows and want to _connect_ to the database
(via ODBC or ADO) and run queries that will fetch/manipulate data on
the database and return it to Excel.

You'll use Excel to further manipualte the returned data -- either more
calculations and/or formatting.

You would not _normally_ shell into the remote db box, but it would be
nice if you could, for whatever reason, to get at or to manipulate the
data.

Depending on just what you need to do, you would usually use stored
procedures or UDFs on the db to provide back end calculations. You
_might_ need to invoke an app on the back end to provide custom
procedures not readily available via db stored procs. This too can
usually be accomplished via the facilities of the db, but not always in
a "reasonable" fashion, ie., it might be easier just to run an app
directly from a remote shell (or web browser).

Depending on your familiarity/comfort with Linux and databases you have
several choices:

-- MySQL will first come to mind as it's all the rage. It _is_ fast
for _some_ applications and has tools available to set it up and
maintain it. It does _not_ provide what I consider to be essential
data integrity features needed by a capable _relational_ SQL db.
Perhaps your data will not require extensive use of multiple, related
tables and foreign keys. Runs well on both Linux and Windows, but the
Windows license may be prohibitive for you. Stored procs/triggers?

-- PostgeSQL has acquired renewed, capable life in the last few years
and _does_ support relational integrity features as well as stored
procs and supports multiple procedure languages. For your particular
needs it may be the way to go for this reason. It's new to Windows and
I'm not sure of all its connection options. My limited experience has
been good, but it may prove overwhelming at first.

-- Firebird has robust data integrity features, stored procs (via its
own stored proc language), and runs quite well on Windows and Linux.
The Linux toolset is slim, especially compared to what's available on
Windows. It supports ODBC and ADO connections. It's lightweight and
one of the easiest dbs to maintain that I've used. I try to use it
(prefer it, more familiar with it) whenever I can as it's
multi-platform support is good both for development and deployment.
Transaction support (OLTP) unsurpassed, IMO.

You'll have to be _explicit_ about the kinds of libraries you're
seeking as I doubt anyone around here has done extensive
financial/stock market data crunching in a commercial setting. Seems
I've read someone claiming some relevant background, but don't remember
who.

I use Python for some (lightweight) math work but it has several very
capable (low level?) libraries available for it. It's used extensively
in bioinformatics work. You can probably find similar libraries on
Perl.

Other than spreadsheets, the only other financial package I've _played_
with runs via the R language, Rmetrics. R runs on Windows as well as
Linux and has several other packages available that might interest you,
viz., working with web servers.

Which brings up the last consideration. If you have any possible need
to provide a client front end other than Excel, eg., custom application
on the client or web based access via a browser, you'll want to
consider the development tools available and how well the db works with
things like PHP or other server scripting environments (Zope, Perl,
Python).

For Excel clients, just set up and try some simple tests, via localhost
db servers and ODBC/ADO, should tell you what's worth investigating
further.

If you go the route that chub suggested, ie., provide your own
client/server apps/libraries, connection management, and data tranfer
you may have quite a bit of work ahead unless you keep it pretty simple
and use available networking libraries with Python or Perl. Many
people are (over?)using web server/interfaces to avoid this detail work
by relying on the infrastructure provided by web (application) servers.
A hammer to swat a fly? Price of flexibility?

some links to R libraries:
http://www.r-project.org/
http://www.itp.phys.ethz.ch/econophysics/R/
http://lib.stat.cmu.edu/S/
http://franklin.imgen.bcm.tmc.edu/R.web.servers/
http://research.warnes.net/projects/rzope

db links:
http://dev.mysql.com/downloads/mysql/4.1.html
http://www.postgresql.org/
http://www.ibphoenix.com/main.nfs?a=...e=ibp_download
http://www.ibphoenix.com/main.nfs?a=...ntrib_download

hth,
prg

>
> some links to R libraries:
> http://www.r-project.org/
> http://www.itp.phys.ethz.ch/econophysics/R/
> http://lib.stat.cmu.edu/S/
> http://franklin.imgen.bcm.tmc.edu/R.web.servers/
> http://research.warnes.net/projects/rzope
>
> db links:
> http://dev.mysql.com/downloads/mysql/4.1.html
> http://www.postgresql.org/
> http://www.ibphoenix.com/main.nfs?a=...e=ibp_download
> http://www.ibphoenix.com/main.nfs?a=...ntrib_download
>

Thanks for your reply mate. Much appreciated. Will try going down the database triggers route
and see how that works.

cheers

Andrew