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Research Positions at the Technical University of Valencia
by Jose Hernandez-Orallo 22 Sep '03

22 Sep '03

Invitation for Applications Department of Computer Science – ELP group Technical University of Valencia (Spain) TWO research positions are available in the STREAM Project (Formal Software Tools: A Multi-paradigm approach) led by Maria Alpuente. The positions are for one year starting January 2004. Salary: 1400 euros per month (net income). An extra initial amount of 1800 euros for travelling and settling. Our department (http://www.dsic.upv.es) is ranked as the third best computing department in Spain. The Technical University of Valencia (http://www.upv.es) is also ranked as the third best Technical University in the country. Valencia is a lively city on the Mediterranean Sea. It has a population of about one million people and there is a great variety of cultural, artistic, scientific and tourist facilities. Accommodation and the cost of living are not high. The ideal candidates should hold a relevant degree in computer science or related disciplines, with high gpa (grade point average). A background in software development in advanced program environments is also recommended. A basic knowledge of declarative programming as well as a great interest in this particular area will be valued. Fluent English, Spanish, Italian or French required. We especially encourage women to apply. It may be possible to combine these positions with PhD studies in Valencia. Continued financial support after the first year period is expected to be available. The duties and activities to be performed include some of the research areas related to the project: * Multi-paradigm declarative programming. * Program analysis, specification, verification, debugging, learning, certification and transformation. * Data mining, decision support systems. * Advanced programming environments, component technologies. Other research activities and further information from the ELP group can be found at (http://www.dsic.upv.es/users/elp/elp.html) Please contact jorallo(a)dsic.upv.es or mramirez(a)dsic.upv.es before October 8, 2003 if you are interested. Use the subject reference “ELP Research Positions” and include a letter of application, curriculum vitae showing your degree qualifications, two references, and any other relevant documentation to support your candidacy for the position.

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RE: echoing of getChar, getLine, getContents
by Simon Marlow 22 Sep '03

22 Sep '03

> The report states about getChar, getLine, and getContents: > > "By default, these input functions echo to standard output." > > In version 1.3 of the report, it used to continue > "Functions in the I/O library provide full control over echoing." > > Apparently, this has been removed and the I/O library contains > neither facilities to control echoing nor a specification of what the > h-cousins hGetChar, hGetLine, and hGetContents are supposed to do wrt > echoing. Can I rely on them not to echo their inputs? Clearly the report is vague here, so I'll just comment on what GHC does. By default, input from a terminal will echo. The following functions are provided by System.IO (GHC only, not Hugs or NHC), and control terminal echoing: hSetEcho :: Handle -> Bool -> IO () hGetEcho :: Handle -> IO Bool Input from a non-terminal will not echo. GHC's IO library never does any actual echoing itself, it simply gives hints to the OS's terminal API to turn echoing on or off. Cheers, Simon

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Fw: cannot find -lreadline
by Luc Taesch 22 Sep '03

22 Sep '03

sorry, repost. ----- Original Message ----- From: "Luc Taesch" <list(a)taesch.com> To: <glasgow-haskell-users-request(a)haskell.org> Sent: Tuesday, September 16, 2003 8:06 AM Subject: cannot find -lreadline > > > when compiling HaXML with 6.01 on mandrake, I got > /usr/bin/ld: cannot find -lreadline, as detailled hereafter. > > also , when I installed the rpm I also got a message on readline missing, despite it is installed. > > is anybody aware of this issue ? any variable to set ? on mandrale, readline is on /lib/libreadline.so.4.3. what about redhat ? > > thanks , Luc > > > [test@localhost HaXml-1.09]$ rpm -ql readline > /lib/libhistory.so.4 > /lib/libhistory.so.4.1 > /lib/libhistory.so.4.2 > /lib/libhistory.so.4.3 > /lib/libreadline.so.4 > /lib/libreadline.so.4.1 > /lib/libreadline.so.4.2 > /lib/libreadline.so.4.3 > [test@localhost HaXml-1.09]$ > > nstance.hs, ../Text/XML/HaXml/DtdToHaskell/Instance.o ) > Skipping Main ( DtdToHaskell.hs, ./DtdToHaskell.o ) > Linking ... > /usr/bin/ld: cannot find -lreadline > collect2: ld returned 1 exit status > make[1]: *** [../../DtdToHaskell] Error 1 > make[1]: Leaving directory `/home/test/Documents/test/HaXml-1.09/obj/ghc' > make: *** [tools-ghc] Error 2 > >

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E-Cap2004_Italy Call for papers
by Lorenzo Magnani 22 Sep '03

22 Sep '03

CALL FOR PAPERS ********************************************************************** COMPUTING AND PHILOSOPHY E-CAP2004_ITALY Pavia, Italy, Collegio Ghislieri, June 3-5, 2004 ********************************************************************** Up-to date information on the conference will be found at http://www.unipv.it/webphilos_lab/courses/progra2.html ********************************************************************** ALSO NEW !! Conference MODEL-BASED REASONING IN SCIENCE AND ENGINEERING Pavia, December 2004 http://www.unipv.it/webphilos_lab/courses/progra1.html ********************************************************************** GENERAL INFORMATION From Thursday 3 to Saturday 5 June 2004 (three days) the International European Conference ``COMPUTING AND PHILOSOPHY'' will be held at the University of Pavia (near Milan, Italy). GENERAL INFORMATION The Computational Philosophy Laboratory and the Department of Philosophy of the University of Pavia will be hosting the European Computing and Philosophy (CAP) conference from the 3rd to the 5th of June. PROGRAM The conference will deal with all aspects of the "computational turn" that is occurring within the discipline of Philosophy. The Programme Committee are particularly interested in submissions in Cognitive Science, Epistemology and Metaphysics. RELEVANT RESEARCH AREAS We call for papers that cover topics pertaining to computing and philosophy from the following list: * Cognitive Science, Epistemology, and Metaphysics * Abductive reasoning, Scientific discovery, Creative processes * Internal and External Representations in Cognitive Science * Simulation, Embodiment, and Distributed Reasoning in Computational Models of Cognitive * Problem of Consciousness in PhilosophyI * New Models of Logic Software * Computer-based Learning and Teaching Strategies and Resources * Ethics * The Impact of Distance Learning on the Teaching of Philosophy * The Role of Computers as Tools for Philosophical Research SUBMISSIONS OF PAPERS The deadline for submission is 19th December 2003 - though late submissions will be considered. Papers submitted for contributed sessions or poster presentations must not exceed a total word count of 3500 words. Papers must be accompanied by a word count and an abstract of not more than 500 words (to be included in the conference program booklet). Authors may submit only one paper and should submit it in either RTF or PDF format by using the MANAGEMENT SYSTEM (in http://www.unipv.it/cap2004) The MANAGEMENT SYSTEM (Registration, Accommodation, Submissions, Participants and Reviewers) in http://www.unipv.it/cap2004 Conference Email Address: infoCAP04(a)unipv.it in case of problem with the above address please use lmagnani(a)unipv.it or lmagnani(a)cc.gatech.edu or elena(a)acrossevents.com REGISTRATION AND FURTHER INFORMATION (to register please use the Management System, in http://www.unipv.it/cap2004 Registration Fees: Before 15 April 2004: Standard: ? 150,00 (to participate in all the activities of the Conference Reception Included) Phd Students: ? 90,00 Students: Free After 15 April 2004: Standard: ? 180,00 (to participate in all the activities of the Conference Reception Included) Phd Students: ? 110,00 Students: Free One day only: ? 80,00 No refunds will be granted after May 12th, 2004 Terms & Conditions: an administration fee of ? 75,00 will be charged for cancellations confirmed in writing by 12th May. We regret that no refund can be made after that date, for whatever reason, although substitutions will be acceptable if notified in writing before the event. ACCOMMODATION (to book a reservation please use the Management System, in http://www.unipv.it/webphilos_lab/courses/progra2.html) All accomodation is hotel-based with en-suite facilities. Hotel Moderno **** EURO 100,00 (single b&b) EURO 135,00 (double b&b) Hotel Ariston *** EURO 80,00 (single b&b) EURO 110,00 (double b&b) Hotel Excelsior *** EURO 50,00 (single) EURO 73,00 (double) EURO 62,00 (D/S) breakfast EURO 6,00 A very limited number of less expensive rooms is available in the several Colleges (some of them historical) of the ancient University of Pavia. IMPORTANT DATES Submission deadline...........................19 December 2003 Notification of acceptance................... 19 March 2004 Conference................................... 3-5 June 2004 Final papers............................due.. 15 July 2004 PROGRAM CHAIR Lorenzo MAGNANI Professor of Logic and Epistemology Department of Philosophy and Computational Philosophy Laboratory University of Pavia, Piazza Botta 6, 27100 Pavia, Italy Office: +39-0382-506283, Home: +39-0383-371067 Fax: +39-0382-23215 & Weissman Distinguished Visiting Professor Department of Philosophy, Baruch College, 1 Bernard Baruch Way, New York , NY 10010 Office: +646-312-4367, Fax: +646- 312-4361, Home: 646-432-9309 Email: lmagnani(a)unipv.it, lmagnani(a)cc.gatech.edu PROGRAM COMMITTEE (provisional, TO BE UPDATED) - Atocha Aliseda, Instituto de Investigaciones Filosoficas Universidad Nacional Autonoma de Mexico (UNAM), Mexico City, MEXICO e-mail: atocha(a)minerva.filosoficas.unam.mx - Diderik Batens, Centre for Logic and Philosophy of Science, Universiteit Gent, Ghent, Belgium e-mail: Diderik.Batens(a)rug.ac.be - Robert Cavalier, Department of Philosophy, Carnegie Mellon, Pittsburgh, PA, USA e-mail: rc2z(a)andrew.cmu.edu - Simon Colton, Department of Computing, Imperial College London, London, UK e-mail: sgc(a)doc.ic.ac.uk - Roberto Cordeschi, Department of Philosophy, University of Salerno, Salerno , ITALY e-mail: cordeschi(a)caspur.it - Chris Dobbyn, Faculty of Maths and Computing,The Open University,Walton Hall, Milton Keynes MK7 6AA e-mail: c.h.dobbyn(a)open.ac.uk - Roy Dyckhoff, School of Computer Science,University of St Andrews,North Haugh, St Andrews,Fife, KY16 9SS, Scotland e-mail: rd(a)dcs.st-and.ac.uk - Luciano Floridi, Wolfson College, University of Oxford, Oxford, UK and University of Bari,Bari, ITALY e-mail: luciano.floridi(a)philosophy.oxford.ac.uk - Theo Kuypers, Dept. of Philosophy, University of Groningen, Groningen, The Netherlands e-mail: T.A.F.Kuipers(a)philos.rug.nl - Lorenzo Magnani, Department of Philosophy, University of Pavia, Pavia, ITALY and Baruch College, The City University of New York, New York, USA e-mail: lmagnani(a)unipv.it, lmagnani(a)cc.gatech.edu - Nancy J. Nersessian, College of Computing, Georgia Institute of Technology, Atlanta, GA, USA e-mail: nancyn(a)cc.gatech.edu - Claudio Pizzi, Department of Philosophy and Social Sciences, University of Siena, Siena, ITALY e-mail: pizzic@unisi.it,claudiopizzi@everyday.com - Susan Stuart, Humanities Advanced Technology and Information Institute, University of Glasgow, Glasgow, UK e-mail: S.Stuart(a)philosophy.arts.gla.ac.uk - Guglielmo Tamburrini, Department of Philosophy, University of Pisa, Pisa, ITALY e-mail: gugt(a)inwind.it - Riccardo Viale, Fondazione Rosselli,Via San Quintino, 18/c, 10121 Torino, Italy e-mail: riccardo.viale(a)fondazionerosselli.it LOCAL ORGANIZER dr. Elena Gandini Across Events s.r.l. Via A. Moro, 12 27021 Bereguardo (PV) Italy mobile +39 349 55 41 915 e-mail: elena(a)acrossevents.com www.acrossevents.com LOCAL ORGANIZING COMMITTEE Elena Gandini (elena(a)acrossevents.com) Alberto Gatti (gatti_alberto(a)hotmail.com) Riccardo Dossena (riki.dox@libero.it),Lorenzo Magnani (lmagnani(a)cc.gatech.edu) Matteo Piazza (pimat(a)yahoo.com) (Department of Philosophy, University of Pavia, Pavia, Italy) IMPORTANT ADDRESSES PROGRAM CHAIR Lorenzo MAGNANI Department of Philosophy and Computational Philosophy Laboratory University of Pavia, Piazza Botta 6, 27100 Pavia, Italy Office: +39-0382-506283, Home: +39-0383-371067 Fax: +39-0382-23215 Email: lmagnani(a)unipv.it also Department of Philosophy, Baruch College, The City University of New York 1 Bernard Baruch Way, New York , NY 10010 Office: +646-312-4364 Fax: +646- 312-4361 CONFERENCE SITE: Collegio Ghislieri, Piazza Ghislieri, 27100 PAVIA, Italy, phone +39 0382 37861. http://www.ghislieri.it/ The Conference is sponsored by UNIVERSITY OF PAVIA, ITALY UNIVERSITY OF SIENA, ITALY MIUR (Ministero dell'Università e della Ricerca Scientifica e Tecnologica), ITALY HOW TO REACH PAVIA LINATE Airport: www.sea-aeroportimilano.it/linate People arriving by plane at LINATE should take the bus to the CENTRAL STATION of Milan (cf. below from this Station to Pavia). In LINATE it could be convenient to take a Taxi because the airport is close to the center of Milan. Moreover,the bus company SGEA ( www.sgea.it ) offers six runs from LINATE to Pavia at 9.00, 10.00, 12.00 AM and 2.00, 5.00, 8.30 PM. The last stop is Pavia, near the station (see again our updated web page for possible alterations of this time-table) (from Pavia to LINATE six runs at 5.00, 7.30, 10.00 AM, 1.00, 4.00, 6.00 PM) (one hour trip; _13,00 return ticket, _8,00 one way ticket). In Pavia there is only one station. The easiest way to reach the center of the town is to get off at the station and than take the bus n. 3. MALPENSA 2000 and OLD MALPENSA Airports: www.sea-aeroportimilano.it/malpensa (usually people arrive to Malpensa 2000 and not to OLD MALPENSA): People arriving by plane at MALPENSA 2000 (also called MALPENSA 2000 Terminal 1) or at "old" MALPENSA (now called MALPENSA NORTH but also called Malpensa 2000 Terminal 2) should take the bus to the CENTRAL STATION of Milan. There is also a bus AND A shuttle TRAIN (Malpensa Express) from Malpensa 2000 to the NORTH STATION (Piazzale Cadorna) of Milan, in this case from NORTH Station you will have to take the underground MM2 (green line) to the Central Raylway Station: trains to Pavia leave from Central station. Moreover, the bus company SGEA offers various runs from MALPENSA 2000 to Pavia at 9.00, 11:00 AM, 1:30 3:00, 5:00, 7:00, 9:30, PM (from Pavia to MALPENSA 2000 and to OLD MALPENSA various runs at 7.00, 9:00, 11:00 AM, 1:00, 3:15, 5:00, 7:00 PM) (one hour and half trip; _18,00 retourn ticket, _12,00 one way ticket). The last stop is Pavia, near the rail station In Pavia there is only one rail station. The easiest way to reach the center of the town is to get off at the station and than take the bus n. 3. There are trains from MILAN (Central Raylway Station) to PAVIA and vice versa about every an hour www.trenitalia.it (routes: MILAN-GENOVA; MILAN-VENTIMIGLIA; MILAN-LA SPEZIA; MILAN-SAVONA; MILAN-SESTRI LEVANTE; MILAN-IMPERIA; MILAN-ALBENGA; Pavia is the first stop only if the train is not slow, that is, if it is not, in ITALIAN, "L", locale). (see again our updated web page for possible alterations of this time-table) For any further information do not hesitate to contact our local organizer, Elena Gandini at elena(a)acrossevents.com

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Announce: wxHaskell 0.2
by Daan Leijen 19 Sep '03

19 Sep '03

Announcement: wxHaskell version 0.2 ---------------------------------------------------------------------- <http://wxhaskell.sourceforge.net> The new release has (improved) support for tree controls, list controls, toolbars, splitter windows, sliders, gauges, and bitmap buttons. Screenshots of these widgets on different platforms have been added to the website. Furthermore, there are numerous small bug fixes, especially for wxGTK. A list of non-compatible changes is attached at the end of this mail. ---------------------------------------------------------------------- wxHaskell is a portable GUI library for Haskell. The goal of the project is to provide an industrial strength portable GUI library, but without the burden of developing (and maintaining) one ourselves. wxHaskell is therefore build on top of wxWindows -- a comprehensive C++ library that is portable across all major GUI platforms; including GTK, Windows, X11, and MacOS X. Furthermore, it is a mature library (in development since 1992) that supports a wide range of widgets with native look-and-feel, and it has a very active community (ranked among the top 25 most active projects on sourceforge). Since most of the interface is automatically generated from the wxEiffel binding, the current release of wxHaskell already supports about 75% of the wxWindows functionality -- 2766 methods in 505 classes with 1279 constant definitions. wxHaskell has been build with GHC 6.0/6.01 on Windows, MacOS X and Unix systems with GTK. A binary distribution is available for Windows and MacOS X. And even if you don't intend to write GUI's yourself, it will be fun to check out the screenshots at <http://wxhaskell.sourceforge.net>. All the best, Daan Leijen. ps. More funny statistics: the wxWindows libraries have been downloaded over a million times at sourceforge! The Python binding to wxWindows (wxPython) about 600.000 times, and the Haskell binding to wxWindows about 100 times :-) ---------------------------------------------------------------------- Breaking changes to version 0.1: - Renamed the "WXH" layer to "WXCore". > import Graphics.UI.WXCore instead of > import Graphics.UI.WXH - Changed the interface of menu items a bit. The label and help text is now supplied via attributes: > medit <- menuPane [text := "&Edit"] > mfont <- menuItem medit [text := "&Font...\tCtrl+F" > ,help := "Set the font"]

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RE: Syntax extensions (was: RE: The Future of Haskell discussionat the Haskell Workshop)
by Simon Marlow 18 Sep '03

18 Sep '03

> {-# LANGUAGE <specification> #-} > > where <specification> is one or more (if compatible) of keywords like > > Haskell98 Pure Haskell 98, no extensions. > SharedExtenisons (Haskell02???) A set of agreed-upon extensions > implemented by all "major" > Haskell systems. > RecursiveDo > ArrowSyntax > TemplateHaskell > OverlappingInstances > UndecidableInstances > FFI Foreign Function Interface > MPTC Multi-parameter Type Classes Looks fine to me. A few things to think about: - Some of the keywords specify an entire language (eg. Haskell98), whereas some are language modifiers (eg. FFI). We might want to make a distinction. Currently GHC supports only Haskell98 + modifiers. - Are extensions always additive? Are there any extensions which are incompatible? - There are features you might want to *disable*. eg. GHC lets you turn off the monomorphism restriction. Perhaps something like this: {-# LANGUAGE Haskell98 +FFI -MonomorphismRestriction #-} > (abbreviations used when three or more words). > > The OPTION pragma would be used for compiler-specific > options, although, > in the interest of supporting portable code without having to > resort to > preprocessing using CPP, maybe it would make sense to provide > > OPTIONS-GHC > OPTIONS-Hugs > OPTIONS-NHC > ... > > as well, the idea being that a compiler/interpreter then only > would look at options pertinent to itself. Yes, I've been meaning to rename GHC's version of the pragma to GHC_OPTIONS for some time. Cheers, Simon

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Re: Syntax Extensions (and future Haskell)
by b.i.mills＠massey.ac.nz 18 Sep '03

18 Sep '03

Ton, Henrick, > | The importance of Haskell is [...] the emphasis it puts on the > | manner in which the total function is decomposed. [...] > Would the picture be less gloomy if you said "the emphasis I put on..." > rather than "the emphasis [Haskell] puts on..."? At first reading, I would have said no, but I get your point. As long as pure sub-Haskell exists, I can still write pure code. > I think most Haskeller's, agree with you: we would like to strive > for uniformity. But how does one get there, how does one agree > on agreeing? A large part of the answer, I think, is through > experiments, i.e. experimental language features, [...] > And in order to find *good* answers to such questions, one needs > to make use of these features in pretty serious projects, which > in turn implies that there has to be a reasonable way of enabling > and disabling them. And command line arguments just isn't a very > good way of doing that in practice. You've both made good points, which I accept. Although I remain wary of these things becoming too much a part of the pragmatic usage and getting locked in as standard behaviour for applications. But, you've convinced me that goal of concptualy pure pragmatic programming is still a feature of the group. Wiping nose on sleeve, I withdraw to write some more geometric software. Regards, Bruce.

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Re: Syntax Extensions (and future Haskell)
by b.i.mills＠massey.ac.nz 18 Sep '03

18 Sep '03

Although a number of comments in this discussion make some sense, I personally am getting worried about the direction that it is taking. I have been a (fairly quiet) Haskell user for some time. I like it because of the strong connection to standard mathematical constructs, and the dedication to equational reasoning. I was dubious when Monads were introduced, but grew to be comfortable with that as an approach to embedding temporal characteristics, I try not to use do, I like the fact that I don't have to. But, recent developments on this list suggest that this is all going to be a thing of the past. There is a real danger that Haskell will just turn into yet another procedural language. Firstly I want to bring into the open something that you would all be aware of. It is possible to change any typical procedural imperative language into a functional language by a change of point of view. All you do is just state that each command in the imperative is a function that operates on the state of the machine. The entire program becomes a composition of these functions. Control statements such as for-do-while-until-repeat-if, simply become higher order functions. That's why the monad stuff works, all it does is demand that you explicitly admit to the passing of the state. If you keep going the way you are going you will simply turn Haskell into a procedural language with some snazzy data-types. It would survive, perhaps, but in name only. The importance of Haskell is not that it is Functional, this is in reality just a technicality of point of view, the importance of Haskell is the WAY in which it is functional, the emphasis it puts on the manner in which the total function is decomposed. It is important not simply that Haskell admits equational reasoning, but that it is equational reasoning that a human can do, not something that requires a heavy duty code transformer to work out. At least this is how I see it, perhaps this is simply the point at which Haskell and I part company? I also don't see the point of the language configuration pragmas either. Uniformity is important. Instead of agreeing to disagree, and coming up with a rag-bag language, the points need to be nutted out until they make consistent sense. The pragmas do not represent any uniformity, they actually represent a schism, you can't agree so you are splitting the language into incompatible variants. It solve the political problem of in-fighting, but only by letting the in-fighting destroy the language. It's the same sort of thing that splits C++ into multiple camps, the same thing that gives the multiple levels of comments in comments for postscript, and so on. Remember Flon's law. The fact that you CAN do something does not mean that it is a good idea. I'll get off my soap box now. Regards, Bruce. ------------------------------------------------------------------------- Institute for Information and Mathematical Sciences Massey University at Albany, email: B.I.Mills(a)massey.ac.nz web: http://www.massey.ac.nz/~bimills -------------------------------------------------------------------------

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How can I implement this arrow? Thanks
by Yu Di 17 Sep '03

17 Sep '03

Hi, I want to create an arrow which is essentially data MyArrow a b = MyArrow ((String, a) -> (String,b)) i.e. there is an "information" asscioated with each piece of data (represented by the string), and I want to pass it around. But I have a problem about how to define "pure" and "first". At first, I declared pure f = MyArrow (\(s, x) -> (s, f x)) first (MyArrow f) = MyArrow (\(s, (x, y)) -> let (s', z) = f (s, x) in (s', (z, y))) this seems to work, but then I begin to have problems with the "data-plumbing" pure arrows, e.g. in pure (\x -> (x, x)) >>> first someArrow >>>> pure (\(_, x) -> x) Ideally, this arrow will preserve whatever information I put there for the input, but because "first someArrow" will change the whole information associated with the pair of result, I can't find any way to let "pure (\(_, x)->x)" (which is an extremely generic function) retrieve the part of information for the second piece in the pair tuple. Of course I can create specialized arrows for the tasks \x -> (x, x) and \(_, x) -> x which passes the information around, but this will become tedious as I will have to define specialized arrows for a lot of similar tasks one by one, and I won't be able to use the arrow pre-processor at all. So how can I implement this? Thanks very much! Di, Yu 9.15 _________________________________________________________________ Get 10MB of e-mail storage! Sign up for Hotmail Extra Storage. http://join.msn.com/?PAGE=features/es

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Improvement on this function
by Gordon James Miller 17 Sep '03

17 Sep '03

Hello all. I'd be interested in getting some feedback on how to do this linear interpolation function a little more cleanly. The normal way that this is taught is to find the set of indices in the x list that bracket the input value, then use the slope between these points to calculate the y value for the input value. I had a version working at one point using !! to access particular elements but I wasn't sure which one was the better solution. linterp :: [Double] -> [Double] -> Double -> Double linterp (x1:x2:xs) (y1:y2:ys) x | x <= x2 || xs == [] = linterpPair x1 x2 y1 y2 x | otherwise = linterp (x2:xs) (y2:ys) x where linterpPair x1 x2 y1 y2 x = x1 + (x - x1) * (y2 - y1) / (x2 - x1) Gordon James Miller Promisemark, Inc. Senior Computer Scientist gmiller(a)promisemark.com (571)330-9012 Light travels faster than sound. That is why some people appear bright until you hear them speak.

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