krj@na.toronto.edu (Ken Jackson) (03/11/89)
From: nagmag%ukc.ac.uk@NSS.Cs.Ucl.AC.UK Date: Fri, 10 Mar 89 10:09:10 EST Subject: NAgMAg V89 #4 Source-Info: From (or Sender) name not authenticated. Sender: trh%ukc.ac.uk@NSS.Cs.Ucl.AC.UK NAgMAg Friday, March 10 1989 Volume 89 Issue 4 Today's Topics Linear Programming - a new software announcement Re: GAMS Classification Scheme Nested calls to D01AJF Reply: NAG Graphical Supplement for NOS/VE Convective Boundary problems Toolpack Mailing list Problem with D02EBF %% Just a couple of things before you get to the interesting %% stuff. Thanks to NAG staff for answering queries but please %% would you send a copy of the reply to nagmag as well %% as the original poster of the query just %% in case other readers are interested in the reply. %% %% I'll also keep a list of unanswered (via nagmag) queries %% here -- just as a gentle reminder:-) %% If individuals have had a reply from NAG please forward %% them to me for inclusion in the digest. %% %% UNANSWERED QUERIES %% ================== %% %% V89 #3 Online Workstation Help System %% V89 #3 GAMS Scheme --------------------------- Date: 2-MAR-1989 14:57:53 GMT From: DAVID@vax.nag.co.uk Subject: Linear Programming - a new software announcement NAGUA members may be interested to hear of the latest software announcement from NAG. Below please find an extract from the first draft of an information note on FORTLP. Within the next few weeks an information pack will be posted to the 50 or so sites who have already expressed a keen interest in the software. If you would like to be included in this mailshot please contact David Sayers at NAG. FORTLP Linear Programming Package - Information Note Introduction. The NAG Library contains excellent routines for the solution of dense linear programming problems. It also has an instructive routine to solve small integer linear programming problems. For many applications however the problem size becomes very large and the NAG routines are no longer the most appropriate. Firstly because sparse techniques are not employed and secondly because the user-interface demands industry-standard data formats. This gap in the NAG problem solving environment has now been admirably filled by FORTLP, a flexible package, originating from Brunel University and which is now available from NAG. The FORTLP Product Nag is offering the FORTLP software in its Fortran source form on a variety of media. It has been successfully tested and installed on a number of machine ranges including IBM PC, DEC Vax and Cray systems. The system is therefore suitable for all classes of machines ranging from PC to supercomputer. The only additional requirement of user site is the availability of a Fortran compiler capable of accepting INTEGER*2 constructs. (This is outside the Fortran standard but is commonly available with most compilers and is exploited by the software to enable it to handle very large problems with maximum efficiency.) Uniquely amongst the NAG offerings FORTLP rests between a package, which solves a users problem given the data, and a collection of subroutines to enable the user to tailor the solution to his own particular requirements. The installation guide explains both uses and the accompanying manual gives considerable internal detail on the working of the system. The Support Service An optional support service is offered and this will entitle the user to periodic updates as the system continues to expand and develop. For example the next release, planned for summer 1989, will include the Forrest and Tomlin LU update for even better preservation of sparsity. We believe that the high quality research into algorithms and software and prospects for further technological breakthroughs, such as the full exploitation of the sparse BLAS concept, make the Support Service an attractive proposition for most sites. March 1989 --------------------------- Date: Fri, 3 Mar 89 14:26 GMT From: FRIEDLI@czheth5a.earn Subject: Re: GAMS Classification Scheme In response to Tim's inquiry (V89 #2): I was in contact with David Kahaner recently and he informed me that they are in the process of editing a new version of GAMS which will include the ACM algorithms and other new things as well. The new volume will appear either this summer or towards the end of the year. Armin Friedli, Friedli@czheth5a.BITNET, ETH Zurich. --------------------------- Date: 6-MAR-1989 14:06:36 GMT From: PHYHJR@vaxb.heriot-watt.ac.uk Subject: Nested calls to D01AJF We had a rather nasty experience using D01AJF recently. The problem took a long time to track down and seems to be due to the use of the common block AD01AJ. It appears that calling the routine from within its integrand function does not work. (the integrand contains another integral). In the documentation under Further Comments there is a note `Labelled COMMON block AD01AJ is used by this routine and must therefor e be avoided by the user', perhaps this should be amended to indicate that recursive calls to the routine will not work. Of course such calls may not be standard f77 but many compilers support this. Harvey Richardson e-mail : JANET - phyhjr@uk.ac.hw.clust INTERNET - phyhjr%clust.hw.ac.uk@cunyvm.cuny.edu BITNET - phyhjr%clust.hw.ac.uk@ukacrl.bitnet mail : Physics Department Heriot-Watt University Riccarton, Edinburgh, EH14 4AS, UK. phone : (+44) 031-451-3047 --------------------------- Date: 08 MAR 89 12:18:15 From: Z3000PA@awituw01.earn Subject: Reply: NAG Graphical Supplement for NOS/VE Dear Mr Partl I understand from Guenter Baszenski that the above will be available in about 1 month with the GKS interface as standard. Yours sincerely Tim Nash --------------------------- Date: Thu, 09 Mar 89 10:25:41 GMT From: "Chan Basaruddin <061 720 7263>" <MBBGPTB@cms.umrcc.ac.uk> Subject: Convective Boundary problems I'm solving a parabolic problem in 2-D (which is linear), but it has got a special boundary conditions i.e of hyperbolic type: a (du/dt) + b (du/dx) + (du/dy) = 0. Which nag routine should I employ ? Chan Manchester --------------------------- Date: Fri, 10 Mar 89 13:35:55 GMT From: Tim Hopkins <trh@uk.ac.ukc> Subject: Toolpack Mailing list In case any of you missed to announcement on the news recently, there is an electronic mailing list been set up for discussing Toolpack. It looks as though there are people out there using it at last and thinking about how to improve it. Anyone interested e-mail dph@lanl.gov If you have problems getting through -- mail me and I'll post them on. Tim. ----------------------------- From: "Alphonse P. Magnus" <ANNU76@buclln11.earn> Subject: Problem with D02EBF To: T Hopkins <nagmag-request@ukc.ac.uk> The following ODE solver went into a loop on NAG Mark12 on the IBM 4381 (VM) of Louvain-la-Neuve (we just received Mark13, not yet installed, perhaps the problem has been settled) PROGRAM NGTD02 C test D02EBF REAL*8 T,T0,TEND,Y(2),TOL,W(222) COMMON T0,TEND,N EXTERNAL FC,CJAC,OUT1,OUT2 N=1 C TOL=1.0D-8 T0=0 TEND=1 Y(1)=1 PRINT '('' t0,tend : '',2F15.10)' , T0,TEND IR=0 NJAC=1 T=T0 IFAIL=111 CALL D02EBF(T,TEND,N,Y,TOL,IR,FC,NJAC,CJAC,OUT1,W,222,IFAIL) PRINT *,' ifail=',IFAIL C TOL=1.0D-8 T0=0 TEND=1 Y(1)=1 PRINT '('' t0,tend : '',2F15.10)' , T0,TEND IR=0 NJAC=1 T=T0 IFAIL=111 CALL D02EBF(T,TEND,N,Y,TOL,IR,FC,NJAC,CJAC,OUT2,W,222,IFAIL) PRINT *,' ifail=',IFAIL STOP END SUBROUTINE FC(T,Y,F) REAL*8 T,T0,TEND,Y(N),F(N) COMMON T0,TEND,N C ridiculously simple exemple y'=y F(1)=Y(1) PRINT '('' t : '',F20.15,'' y:'',1PE14.7)',T,Y RETURN END SUBROUTINE CJAC(T,Y,JAC) REAL*8 T,T0,TEND,Y(N),JAC(N,N) COMMON T0,TEND,N JAC(1,1)=1 RETURN END SUBROUTINE OUT1(TSOL,Y) REAL*8 TSOL,T0,TEND,Y(N) COMMON T0,TEND,N PRINT '('' tsol: '',F20.15,'' y:'',1PE14.7)',TSOL,Y TSOL=TSOL+0.1*(TEND-T0) IF( ABS( (TSOL-TEND)/(T0-TEND) ) .LT.1.0D-5) TSOL=TEND C This one works fine RETURN END SUBROUTINE OUT2(TSOL,Y) REAL*8 TSOL,T0,TEND,Y(N) COMMON T0,TEND,N PRINT '('' tsol: '',F20.15,'' y:'',1PE14.7)',TSOL,Y TSOL=TSOL+0.1*(TEND-T0) IF( TSOL.GT.TEND ) TSOL=TEND C should stop here, but runs into a loop RETURN END %% A quick run on the unix version gives the same results. %% Tim --------------------------------------- %% %% Replies or submissions to nagmag@uk.ac.ukc %% Distribution changes to nagmag-request@uk.ac.ukc %% %% END OF ISSUE -------------------------------------- Reposted by -- Kenneth R. Jackson, krj@na.toronto.edu (on Internet, CSNet, Computer Science Dept., ARPAnet, BITNET) University of Toronto, krj@na.utoronto.ca (CDNnet and other Toronto, Canada M5S 1A4 X.400 nets (Europe)) (Phone: 416-978-7075) ...!{uunet,pyramid,watmath,ubc-cs}!utai!krj