jph@suns.UMD.EDU (J. Patrick Harrington) (09/07/90)
I have recently obtained Dyalog APL for one of our Sun 4
computers, and it is indeed an impressive implementation,
especially after limping along with a bug-ridden version of
APL\11. One of the problems with APL is that it seems to be a
universe unto itself, and little consideration is given to the
possibility of interfacing it with other languages/data sets that
may reside on the system. One great feature of Dyalog APL is that
interaction possible using "Auxiliary Processors"; in particular,
the 'unixfiles' AP lets you read a native unix file outside the
APL workspace.
I very soon found that I wanted to make some calculations
based on some data sets - columns of floating numbers - which I
had in non-APL files on the system, and I surely didn't want to
type them in. Well, 'unixfiles' would read them in, but in the
form of nested arrays of characters. I could disclose and decode
the strings of characters to get numeric data - but then there
were the '-' signs! Another AP called 'xutils' contains the
function 'ss' which searches out and replaces strings. So we
replace each '-' with the high minus, and the 'e's with 'E's. So
I wrote a little function that reads in a named unix file and
turns it into a APL numeric array. But it still hangs on the
occasional '0.000E+00' it may find in the unix file.
I would think that reading lists of numbers from files would
be such a basic need that others must have solved this problem.
Is there some neat way to do this?
Another question for those who may be using Dyalog: Our
printers are Apple LaserWriter II's, which isn't one of the
supported printers. Does anyone have experience with this
combination?
J. Patrick Harrington
jph@astro.umd.edusam@ss_csi.jpl.nasa.gov (Sam Sirlin) (09/08/90)
(mail bounced, so I'm posting this) I have had occasion to transfer data between Promatlab on VAX/SUNs to STSC's APL/PC. I read in the data as characters, then substitute - high minus D E (double precision on VAX) e E (SUN exponents) + 0 and then can execute the variable to obtain numerical data. -- Sam Sirlin Jet Propulsion Laboratory sam@kalessin.jpl.nasa.gov Sam Sirlin Jet Propulsion Laboratory sam@kalessin.jpl.nasa.gov sam@jpl-gnc-gw.jpl.nasa.gov
clark@doggerel.gg.caltech.edu (Clark Brooks) (09/08/90)
In <7258@umd5.umd.edu> jph@suns.UMD.EDU (J. Patrick Harrington) writes: > I would think that reading lists of numbers from files would >be such a basic need that others must have solved this problem. >Is there some neat way to do this? And you call yourself an APL programmer. -- clark@csvax.cs.caltech.edu Neuro-linguistic programming is simply the zig-zag and swirl of menorgs and disorgs acting under the suction and pressure of the morphogenetic field. -- Knowledgian maxim
rjfrey@kepler.com (Robert J Frey) (09/10/90)
In article <7258@umd5.umd.edu> jph@suns.UMD.EDU (J. Patrick Harrington) writes: > >...One of the problems with APL is that it seems to be a >universe unto itself...One great feature of Dyalog APL is that >interaction possible using "Auxiliary Processors"... Other implementations of APL have similar facilities, but only APL2's quadNA is comparable in ease of use and flexibility to Dyalog's quadSH. We regularly run 16 Mbyte workspaces on Sun 4's with excellent performance and make heavy use of AP's to improve efficiency and integrate APL with other applications. I've also found the code quite transportable. It took two programmers less than two weeks to transport an application consisting of thousands of lines of both APL and C from Xenix on 386's over to Sun 4's. >[...description of application deleted...] I would think that reading lists >of numbers from files would be such a basic need that others must have >solved this problem. Is there some neat way to do this? From what you describe the simplest thing would be to write an awk program to fix the format before bringing it over to APL! :-) As far as doing it within APL itself, I can offer two suggestions: First, use 'ss' to make the substitutions, eg, '-' -> negative-sign, 'e+' to 'E', etc. then do an 'execute foreach' on the nested character string. Second, encapsulate this stuff into a utility function and stick it somewhere everyone can get at, eg, a LOCAL.UTIL workspace in a lib directory like /usr/lib/WS or whatever convention you use at your site. If it's not clear how do this to all the character vectors in the nested vector in one fell swoop, then figure out how to do it to a single simple character vector, put it in a function, then apply the function with a 'foreach' across the vector. This may work better if there is some messy formatting problems or alot of case-by-case reasoning required. > Another question for those who may be using Dyalog: Our >printers are Apple LaserWriter II's, which isn't one of the >supported printers. Does anyone have experience with this >combination? I would try contacting Dyalog if nothing comes in off the net. Sorry I can't help with this one. > J. Patrick Harrington > jph@astro.umd.edu -- Dr. Robert J Frey, Kepler Financial Management, Ltd. rjfrey@kepler.com *or* frey@chaos.sunysb.edu voice: (516) 689-6300 * fax: (516) 751-8678