Fix PR 11119.

[pspp] / TODO

Time-stamp: <2005-05-16 22:22:15 blp>

Format specifier and missing values code needs to be rewritten for lowered
crappiness.

CROSSTABS needs to be re-examined.

RANK, which is needed for the Wilcoxon signed-rank statistic, Mann-Whitney U,
Kruskal-Wallis on NPAR TESTS and for Spearman and the Johnkheere trend test (in
other procedures).

lex_token_representation() should take a buffer to fill.

Make valgrind --leak-check=yes --show-reachable=yes work.

Add NOT_REACHED() macro.

Add compression to casefiles.

There needs to be another layer onto the lexer, which should probably be
entirely rewritten anyway.  The lexer needs to read entire *commands* at a
time, not just a *line* at a time.  It also needs to support arbitrary putback,
probably by just backing up the "current position" in the command buffer.

Scratch variables should not be available for use following TEMPORARY.

Details of N OF CASES, SAMPLE, FILTER, PROCESS IF, TEMPORARY, etc., need to be
checked against the documentation.  See notes on these at end of file for a
start.

Check our results against the NIST StRD benchmark results at
strd.itl.nist.gov/div898/strd

In debug mode hash table code should verify that collisions are reasonably low.

Use AFM files instead of Groff font files, and include AFMs for our default
fonts with the distribution.

Storage of value labels on disk is inefficient.  Invent new data structure.

Add an output flag which would cause a page break if a table segment could fit
vertically on a page but it just happens to be positioned such that it won't.

Fix spanned joint cells, i.e., EDLEVEL on crosstabs.stat.

Cell footnotes.

PostScript driver should emit thin lines, then thick lines, to optimize time
and space.

New functions?  var_name_or_label(), tab_value_or_label()

Should be able to bottom-justify cells.  It'll be expensive, though, by
requiring an extra metrics call.

Perhaps instead of the current lines we should define the following line types:
null, thin, thick, double.  It might look pretty classy.

Perhaps thick table borders that are cut off by a page break should decay to
thin borders.  (i.e., on a thick bordered table that's longer than one page,
but narrow, the bottom border would be thin on the first page, and the top and
bottom borders on middle pages.)

Support multi-line titles on tables. (For the first page only, presumably.)

Rewrite the convert_F() function in data-out.c to be nicer code.

In addition to searching the source directory, we should search the current
directory (for data files).  (Yuck!)

Fix line-too-long problems in PostScript code, instead of covering them up.
setlinecap is *not* a proper solution.

Fix som_columns().

Has glob.c been pared down enough?

Improve interactivity of output by allowing a `commit' function for a page.
This will also allow for infinite-length pages.

Implement thin single lines, should be pretty easy now.

SELECT IF should be moved before other transformations whenever possible.  It
should only be impossible when one of the variables referred to in SELECT IF is
created or modified by a previous transformation.

The manual: add text, add index entries, add examples.

The inline file should be improved: There should be *real* detection of whether
it is used (in dfm.c:cmd_begin_data), not after-the-fact detection.

Figure out a stylesheet for messages displayed by PSPP: i.e., what quotation
marks around filenames, etc.

New SET subcommand: OUTPUT.  i.e., SET OUTPUT="filename" to send output to that
file; SET OUTPUT="filename"(APPEND) to append to that file; SET OUTPUT=DEFAULT
to reset everything.  There might be a better approach, though--think about it.

From Zvi Grauer <z.grauer@csuohio.edu> and <zvi@mail.ohio.net>:

   1. design of experiments software, specifically Factorial, response surface
   methodology and mixrture design.

   These would be EXTREMELY USEFUL for chemists, engineeris, and anyone
   involved in the production of chemicals or formulations.

   2. Multidimensional Scaling analysis (for market analysis) -

   3. Preference mapping software for market analysis

   4. Hierarchical clustering (as well as partition clustering)

   5. Conjoint analysis

   6. Categorical data analsys ?

IDEAS
-----

In addition to an "infinite journal", we should keep a number of
individual-session journals, pspp.jnl-1 through pspp.jnl-X, renaming and
deleting as needed.  All of the journals should have date/time comments.

Qualifiers for variables giving type--categorical, ordinal, ...

Analysis Wizard

Consider consequences of xmalloc(), fail(), hcf() in interactive
use:
a. Can we safely just use setjmp()/longjmp()?
b. Will that leak memory?
i. I don't think so: all procedure-created memory is either
garbage-collected or globally-accessible.
ii. But you never know... esp. w/o Checker.
c. Is this too early to worry? too late?

Need to implement a shared buffer for funny functions that require relatively
large permanent transient buffers (1024 bytes or so), that is, buffers that are
permanent in the sense that they probably shouldn't be deallocated but are only
used from time to time, buffers that can't be allocated on the stack because
they are of variable and unpredictable but usually relatively small (usually
line buffers).  There are too many of these lurking around; can save a sizeable
amount of space at very little overhead and with very little effort by merging
them.

Clever multiplatform GUI idea (due partly to John Williams): write a GUI in
Java where each statistical procedure dialog box could be downloaded from the
server independently.  The statistical procedures would run on (the/a) server
and results would be reported through HTML tables viewed with the user's choice
of web browsers.  Help could be implemented through the browser as well.

HOWTOs
------

MORE NOTES/IDEAS/BUGS
---------------------

Sometimes very wide (or very tall) columns can occur in tables.  What is a good
way to truncate them?  It doesn't seem to cause problems for the ascii or
postscript drivers, but it's not good in the general case.  Should they be
split somehow?  (One way that wide columns can occur is through user request,
for instance through a wide PRINT request--try time-date.stat with a narrow
ascii page or with the postscript driver on letter size paper.)

NULs in input files break the products we're replacing: although it will input
them properly and display them properly as AHEX format, it truncates them in A
format.  Also, string-manipulation functions such as CONCAT truncate their
results after the first NUL.  This should simplify the result of PSPP design.
Perhaps those ugly a_string, b_string, ..., can all be eliminated.

From Moshe Braner <mbraner@nessie.vdh.state.vt.us>: An idea regarding MATCH
FILES, again getting BEYOND the state of SPSS: it always bothered me that if I
have a large data file and I want to match it to a small lookup table, via
MATCH FILES FILE= /TABLE= /BY key, I need to SORT the large file on key, do the
match, then (usually) re-sort back into the order I really want it.  There is
no reason to do this, when the lookup table is small.  Even a dumb sequential
search through the table, for every case in the big file, is better, in some
cases, than the sort.  So here's my idea: first look at the /TABLE file, if it
is "small enough", read it into memory, and create an index (or hash table,
whatever) for it.  Then read the /FILE and use the index to match to each case.
OTOH, if the /TABLE is too large, then do it the old way, complaining if either
file is not sorted on key.

----------------------------------------------------------------------
Statistical procedures:

For each case we read from the input program:

1. Execute permanent transformations.  If these drop the case, stop.
2. N OF CASES.  If we have already written N cases, stop.
3. Write case to replacement active file.
4. Execute temporary transformations.  If these drop the case, stop.
5. Post-TEMPORARY N OF CASES.  If we have already analyzed N cases, stop.
6. FILTER, PROCESS IF.  If these drop the case, stop.
7. Pass case to procedure.

Ugly cases:

LAG records cases in step 3.

AGGREGATE: When output goes to an external file, this is just an ordinary
procedure.  When output goes to the active file, step 3 should be skipped,
because AGGREGATE creates its own case sink and writes to it in step 7.  Also,
TEMPORARY has no effect and we just cancel it.  Regardless of direction of
output, we should not implement AGGREGATE through a transformation because that
will fail to honor FILTER, PROCESS IF, N OF CASES.

ADD FILES: Essentially an input program.  It silently cancels unclosed LOOPs
and DO IFs.  If the active file is used for input, then runs EXECUTE (if there
are any transformations) and then steals vfm_source and encapsulates it.  If
the active file is not used for input, then it cancels all the transformations
and deletes the original active file.

CASESTOVARS: ???

FLIP:

MATCH FILES: Similar to AGGREGATE.  This is a procedure.  When the active file
is used for input, it reads the active file; otherwise, it just cancels all the
transformations and deletes the original active file.  Step 3 should be
skipped, because MATCH FILES creates its own case sink and writes to it in step
7.  TEMPORARY is not allowed.

MODIFY VARS:

REPEATING DATA:

SORT CASES:

UPDATE: same as ADD FILES.

VARSTOCASES: ???
----------------------------------------------------------------------
N OF CASES

  * Before TEMPORARY, limits number of cases sent to the sink.

  * After TEMPORARY, limits number of cases sent to the procedure.

  * Without TEMPORARY, those are the same cases, so it limits both.

SAMPLE

  * Sample is just a transformation.  It has no special properties.

FILTER

  * Always selects cases sent to the procedure.

  * No effect on cases sent to sink.

  * Before TEMPORARY, selection is permanent.  After TEMPORARY,
    selection stops after a procedure.

PROCESS IF

  * Always selects cases sent to the procedure.

  * No effect on cases sent to sink.

  * Always stops after a procedure.

SPLIT FILE

  * Ignored by AGGREGATE.  Used when procedures write matrices.

  * Always applies to the procedure.

  * Before TEMPORARY, splitting is permanent.  After TEMPORARY,
    splitting stops after a procedure.

TEMPORARY

  * TEMPORARY has no effect on AGGREGATE when output goes to the active file.

  * SORT CASES, ADD FILES, RENAME VARIABLES, CASESTOVARS, VARSTOCASES,
    COMPUTE with a lag function cannot be used after TEMPORARY.

  * Cannot be used in DO IF...END IF or LOOP...END LOOP.

  * FLIP ignores TEMPORARY.  All transformations become permanent.

  * MATCH FILES and UPDATE cannot be used after TEMPORARY if active
    file is an input source.

  * RENAME VARIABLES is invalid after TEMPORARY.

  * WEIGHT, SPLIT FILE, N OF CASES, FILTER, PROCESS IF apply only to
    the next procedure when used after TEMPORARY.

WEIGHT

  * Always applies to the procedure.

  * Before TEMPORARY, weighting is permanent.  After TEMPORARY,
    weighting stops after a procedure.


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