krj@na.toronto.edu (Ken Jackson) (03/24/89)
From: nagmag%ukc.ac.uk@NSS.Cs.Ucl.AC.UK Date: Thu, 23 Mar 89 10:25:39 EST Subject: NAgMAg Vol 89 #06 Sender: trh%ukc.ac.uk@NSS.Cs.Ucl.AC.UK NAgMAg Thursday, March 23 1989 Volume 89 Issue 6 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %% The official electronic digest of the NAG Users Association %% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Today's Topics E01ADF Assistance sought for Mark 3 Graphics Replies to NAGMAG 5 C Software %% Editorial %% %% This digest is going out a day early -- so it can sit in your %% mailbox 'til you've recovered from gorging too many chocolate eggs! %% I'm away next week so the next digest (if there's any input -- HINT) %% will go out sometime during the week beginning April 3. %% %% NAG wish it to be known that this is NOT an official NAG digest but %% it IS an official NAGUA digest -- hence the appearance of the %% boxed comment in the header. %% %% As you will see I have been forced to insert my own articles in %% an attempt to generate some discussion. I don't have an infinite %% supply of these. I just don't believe nobody has anything to say %% about NAG. One or two people have said they are only interested %% in particular areas (e.g., statistics) -- don't be afraid of %% submitting articles I'm sure other readers will be interested. %% %% Have a peaceful Easter. %% Tim --------------------------- Date: Fri,17 Mar 89 16:37:36 GMT From: Bob_Hatfield@vme.ccc.nottingham.ac.uk Subject: E01ADF I have a copy of the documentation for E01ADF if you still haven't found a copy. Bob Hatfield Cripps Computing Centre University of Nottingham --------------------------- Date: Sun, 19 MAR 89 17:28:50 GMT From: DAVID@vax.nag.co.uk Subject: Assistance sought for Mark 3 Graphics Requests for assistance from NAG Graphics Users ----------------------------------------------- 1)Do any of our NAG Graphics users have any data cases and/or programs which generate interesting pictures or illustrate applications to which NAG Graphics has been put? We would like to include examples of 'real usage' of our software in such documentation as advertising material, newsletter articles, displayed on our trade stand, used to illustrate talks about the NAG Graphics etc. We would welcome any contributions of: code (and data), data only or pictoral output (e.g. 35mm slide, good quality hardcopy etc.), preferably accompanied by a brief explanatory description. The source of any contributions would of course be acknowledged if we were to use them. 2) In the Mark 3 Graphics Library Manual we wish to include a section describing common user mis-understandings and the corrective action to take. Below please find a list which NAG have compiled. We believe that many NAGUA members will perhaps have experienced other problems which should be included. If so please let us know and we will see that they appear in the list. Corrective actions for commonly encountered errors. -------------------------------------------------- The following Section has been derived directly as a result of questions received from our user sites about problems encountered when running the NAG Graphics Library. It is hoped that the following table will assist you in identifying the cause of any problems you may encounter when linking or running NAG Graphics. To use this table you should first identify the category of your problem (left hand side of table) and check each of the possible causes listed (right hand side) in turn. Full details associated with each cause are listed following the table (indexed alphabetically). Should you still be unable to resolve your problem after having checked the advice given, you are recommeneded to contact your local NAG site representative for further assistance. Problem Possible Cause ------- -------------- Problems encountered at Link time: Messages are generated indicating Libraries being searched in that there are unresolved external wrong order (a) references (or multiple references) Incorrect routine name used (b) Problems encountered at Run time: Program will not run without Incorrect Parameter(s) generating run time messages supplied (c) e.g. access violations. Wrong base precision used (d) Program was copied from Handbook (e) Wrong compiler version (f) Graphical output is incomplete NAG Graphics has not been terminated correctly (g) Graphical output generated was Wrong base precision used (d) not what was expected Wrong NAG Graphics routine used (h) Incorrect Parameter(s) supplied (c) Site specific modifications made to NAG Graphical Interface (j) Example output plot differs from Incorrect Parameter(s) that printed in the Handbook supplied (c) Underlying plotting software has different attributes from one used by Handbook (Adobe PostScript) (i) Site specific modifications made to NAG Graphical Interface (j) Possible causes - further guidance ---------------------------------- a) Libraries are being searched in wrong order The correct order for linking NAG graphics routines is: NAG Graphics, NAG Graphical Interface, NAG routines, Plotting Software Please check the instructions supplied by your site or contact your site representative for further assistance. b) Incorrect routine name used Check that you have used the NAG naming convention applicable to your site. NAG graphics routine names may end in either F (e.g J06GAF) or E (e.g. J06GAE). Check that you have not mistyped the NAG Graphics routine name. All NAG Graphics routines start with the characters J06 (J-zero-6) not JO6 (J-oh-6); it is easy to mistype this. Please see section 2 of Background Notes for further details. c) Incorrect Parameter(s) supplied Check that you have not supplied an incorrect value for one of the input parameters to your selected NAG Graphics routine; you are advised to check the following: - Your calling sequence(s) matches that given in the associated routine documention. - The type of each variable - That all EXTERNAL subroutines have been declared - The base precision being used for interpreting real variables - That you have supplied sufficient workspace - The dimension of arrays - The order of dimensions for 2D arrays d) Wrong base precision used NAG Graphics routines are available in both single and double precisions. It is normal for a site to make available only one precision version of the Library. If you call NAG Graphics with single precision arguments and the implementation available at your site is double precision your program may behave unpredictably. A program will not necessary fail and a plot may even be generated. A common cause for selecting the wrong precision is copying code or routine parameter specifications directly from the User Handbook without considering the precision of the NAG Graphics Library you are using. The examples and text in the NAG Graphics Library Handbook are printed to reflect single precision implementations. Emboldened terms are used to reflect those elements which need to be converted to double precision Please see section 2 of Background Notes for further details. e) Program was copied from Handbook Typing errors may be the source of your problem. You are advised that your site has a copy of all example programs printed in the Handbook which are specific to your local implementation of the NAG Graphics Library. Please contact your site representative for further details. f) Wrong compiler version selected When linking to NAG Graphics Libraries on some systems, especially Personal computers you should ensure that your compiler is compatible with the implementation NAG have supplied. The following should be checked: - Compiler version - Whether a co-processor is required or not (PC machines) - Whether G-Floating or D-Floating arithmetic is being used You can determine the compiler version of the NAG Graphics Implementation available at your site by calling NAG Graphics routine J00AAF (zero-zero). Please contact your site representative for further assistance. g) NAG Graphics has not been terminated correctly You have omitted to call NAG Graphical Interface routine J06WZF. J06WZF ensures that the underlying plotting software and NAG Graphics are terminated correctly and that all graphical buffers are flushed. h) Wrong NAG Graphics routine selected Check that you have selected the appropriate routine to produce your desired output plot. A Pictoral Guide to using the NAG Graphics Library and detailed guidance in each Chapter Introduction have been provided in the Handbook to assist you in your selection of routines. i) Underlying Plotting Software attributes vary The form of graphical output is very much dependent upon your target device and the NAG Graphical Interface in use. You are recommended to use discretion when judging the acceptability of graphical results. The graphical plots printed in the User Handbook are supplied as examples of the style of output you would expect from the routine. The general form of output generated should match that supplied i.e. the position of lines, textual content, relationship of plot to the viewport etc. should be in a similar position, however differences such as the following can be expected: - Representations of line styles (other than solid) - Marker styles - Text font representation. - Text sizes (particularly if using medium quality (hardware) text. - Colours (of lines or filled areas) - Package supplied fill styles (most example programs supplied use NAG generated fill styles; these should not vary significantly) j) Site specific modifications Your site may have made modifications to the default settings of the NAG Graphical Interface you are using. Any modifications made should be indicated in local documentation. Please contact your site representative for further details. LAC/16-Mar-1989 --------------------------- Date: Sun, 19 MAR 89 18:08:01 GMT From: DAVID@vax.nag.co.uk Subject: Replies to NAGMAG 5 RE: E01ADF NAG keeps copies of the withdrawn routine documentation for these purposes. In brief: SUBROUTINE E01ADF(N,A,X,Y,W,D,IG,VAL) INTEGER N,IG real A,X(IG),Y(IG),W(IG),D(IG),VAL N- the number of intervals ie there are N+1 datapoints X,Y the datapoints (x,y) W,D work arrays A specified point where interpolated value is required VAL on exit contains the answer. Exactly the same answers should not be expected. In the newer routines more natural end conditions were imposed ; earlier software would not reproduce a cubic exactly - a feature that still exists in other libraries I believe. RE: GAMS Ron Boisverts offer is very atractive to NAG. We would hope that MARK 14 would be included. For completeness the Sparse Matrix Library, the NAG Graphics, and the statistical packages GENSTAT and GLIM should be seen alongside the other entries. We would like to take the latest version when it becomes available and make these additions. --------------------------- Date: Thu, 23 MAR 89 15:15:01 GMT From: trh@ukc.ac.uk Subject: C software I was recently assaulted by a colleague waving an advertisement for NAG software which claimed to be able supply numerical s/ware in Fortran/Pascal/ADA and C. What exactly is available in C? Are there any plans to produce a C version of the main subroutine library? If not, why not? Anybody else out there perceive a need for C numerical s/ware? 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