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.MYDATE←DAY&" "&MONTH[1 TO 3]&" "&YEAR[3 TO 4];

.TURN ON "←{"
.GROUP SKIP 12
←READING THE ASSOCIATED PRESS NEWS
.GROUP SKIP 3
←By Martin Frost

←{MYDATE}
.TURN OFF
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.BEGIN INDENT 8,8,8
ABSTRACT:


We have a line from the Associated Press (AP) over which we
get national and international news (no local news).  The line is
read by a program that takes incoming news stories and files them
away on the disk, keeping about 24 hours' worth of news on file at
any given time.  This document (which exists as the file APE.ME[UP,DOC])
describes usage of programs that allow
access to the AP news.
.END

.NEXT PAGE
.EVERY HEADING({MYDATE},AP News,Page {PAGE})

We have a line from the Associated Press (AP) over which we
get national and international news (no local news).  The line is
read by a program that takes incoming news stories and files them
away on the disk, keeping about 24 hours' worth of news on file at
any given time.  This document (which exists as the file APE.ME[UP,DOC])
describes usage of programs that allow
access to the AP news.

For use in reading the news, there are two programs on the
system.  The first of these is HOT, which is a very small program
that simply types out the stories as they come in (at a somewhat slow
rate of 6 2/3 characters/sec).  The second program is APE, which
enables the user to read selectively the news that is on file.

To use the hot line, simply type the monitor command: R HOT.
The program should type back: "...Associated Press news..."; if it
doesn't, then it is having trouble contacting the program [-AP-],
which listens to the AP line.  In this case, the program will try for
thirty seconds to contact [-AP-], after which time it will give up
and tell you so.  After "...Associated Press news..." is typed out,
you will get whatever news is coming in.  (There are times, usually
of only a few minutes duration, when no news is coming in; at such
times, HOT will of course type out nothing.) WARNING: Typing ↑C or
holding the typeout while the news is coming in will probably cause
HOT to miss some characters.  If that happens, your job number will
be scratched from the list of jobs getting the hotline news; so you
will have to restart HOT.

From time to time, you may get stuff from HOT that looks like
garbage; in fact, it IS garbage resulting apparently from a hardware
problem with the teletype line over which the stories come.  When
this happens, it will eventually correct itself, but this may take
anywhere from a few seconds to an hour.

Now before describing the second program (APE), I will
explain a few things about AP news stories.  First of all, each story
has a sequence number which comes at the beginning of the story and a
date and time that come at the end.  The sequence numbers start over
every day, with the first story that comes after midnight EST getting
number 001.  The time at the end of each story is the approximate New
York time when the story was sent over the wire.

Every twelve hours (at noon and at midnight EST) there is a
news digest that summarizes the stories that are known to be coming
in over the next twelve hours.  The digest at midnight is usually
story number 002 and the one at noon usually number 202.  The digests
are (usually) not categorized; to get them you must use one of the
two methods described in paragraph 1 under SPECIAL FEATURES.

Every day there are many stories that are corrections or
additions to previous stories.  We (usually) link up such a follow-up
with the original and treat the resultant combination as one story,
although it may be made up of two, three, or even more separately
numbered stories.  Any attempt to retrieve the original story with APE
will result in retrieval of all follow-ups also.  (A long story will
be broken up into smaller parts by the Associated Press; the smaller
parts are called TAKES and each gets its own sequence number.  We try
to link all takes of the same story together just like additions and
corrections.  Sometimes, however, a take gets linked to some other
story.)



.SEC "The Associated Press Extractor (APE)"

The program that is used to retrieve news is called APE.  It
allows quick access to the stories (without searching) because of a
data structure that is continually being updated by other programs.
As each story comes in over the AP wire, it is catagorized by
keywords; for each keyword a list is kept of all the stories that
word occurs in.  To access the news, you select the keyword or
combination of keywords that you wish to read about.
A keyword can be either a single word (or number) or a sequence of
words (and/or numbers).  For example, the following are some possible
.TURN ON "#"
keywords: WELFARE, WAR, SAN FRANCISCO, UNITED STATES, UNION OF SOVIET
SOCIALIST REPUBLICS, PDP#10, etc.

(The list of keywords contains right now about 1000 words,
mostly people's names and names of places (cities, states,
countries).  This list is expandable, and if you have any words you
would like added to the list, SEND a note to ME.
To see a list of the keywords, TYPE
the file WORDS.SRT[AP,SYS] or SPOOL the file WORDS.LST[AP,SYS].)



.SEC Keyword Expressions


To retrieve stories using APE, you type in a KEYWORD
EXPRESSION, which may be either a single keyword or an expression
containing keywords and the operators +, -, and *.  Each keyword
represents the set of all the stories it occurs in.  And the operators
represent the set operations UNION#(+), INTERSECTION#(*), and SET
DIFFERENCE#(-), which are performed on the sets of stories which the
.TURN OFF
keywords represent.  Thus, if you want all stories that mention both
Nixon and McGovern, you should type the keyword expression
"NIXON*MCGOVERN".  The precedence of operators is the normal one:  *
takes precedence over + and -, which have equal precedence.
Operations which have equal precedence are evaluated from left to
right.  Parentheses may be used freely in keyword expressions.  Note
that + and - are BINARY operators only.

	To clarify all this a little, here are a few examples:

.BEGIN
.TABS 34,38,69
.TURN ON "%" FOR "#"
.TURN ON "∞\←"
.TURN OFF "-"
←Keyword Expression\\←Meaning\

∞-\\∞-\-

.INDENT ,37
(NIXON-WALLACE+MCGOVERN)*ELECTION\\All stories that mention both
ELECTION and either (1) NIXON and not WALLACE or (2) MCGOVERN
(and possibly WALLACE).

ELECTION-NIXON-WALLACE-MCGOVERN\\All stories that mention
ELECTION but that mention none of NIXON, WALLACE and MCGOVERN.

SAN%FRANCISCO+LOS%ANGELES-WAR\\All stories that mention either
SAN FRANCISCO or LOS ANGELES, but not WAR.
.END

Note: Spaces are needed only to separate individual words of multiple
word keywords, but they may be used anywhere
except in the middle of a word or special form.
.SEC Running APE


To run APE, type the monitor command: R APE.  When APE starts
up it reads in various files, and it is possible that another program
will have hold of one of those files.  In that case, APE will say
"One moment please..." and will wait until it can grab the file.
After all the files have been read in, APE will respond with "KEYWORD
EXPRESSION:"; you should then type in a keyword expression as defined
in the last section.  APE will count the stories that match your
expression and tell you how many stories it found, such as:
.BEGIN VERBATIM

		005 news item(s) found.  Read which one(s)?

.END CONTINUE
At this point, you can select any contiguous group from the stories
found.  For example, you can read the oldest 4 stories of those
matching your keywords, or you can read the newest 3, or the 2nd
through the 4th, or all of them, or none of them, etc.  And you can
have the sublist of stories you select typed out only, or you can
have the option of spooling them and/or saving them in a file on your
disk area.  The list below explains the various ways of making your
selection; after the list are some examples.

------------
.BEGIN
.INDENT ,3 ; PREFACE 0
.TURN OFF "-"
.SKIP
To select all the stories in normal order (newest story first), type
nothing (blank line).

To select None of the stories, type "N" (for None).

To select the k newest stories in normal order, type the number "k".

To select the k oldest stories in normal order, type the number "-k".

To select the jth story through the kth story, type "j:k".  Note that
in this construction "1" represents the newest story, larger
numbers represent older stories, "*" represents the oldest story,
and finally, "-k" represents the kth oldest story.  Thus, "-1" is
equivalent to "*"; both represent the oldest story.  The stories
will come out in the order you specify: story j first, story k
last.

To reverse the order in which the stories come out, begin the line
with "=".

To have only the first few lines of each story you select typed out,
type an "F" (for Fast) at the beginning of the line.  (When you
use both the "F" and the "=" features, their order is
arbitrary.)  When you say "F", you cannot spool or save the
stories in a file.

THE SELECTION LINE YOU TYPE SHOULD END WITH EITHER A CARRIAGE RETURN
OR A LINEFEED.  CARRIAGE RETURN will cause the selected stories
just to be typed out.  LINEFEED will give you the chance to save
the stories in a file and/or spool them, in addition to possibly
having them typed out.
.END
.BEGIN VERBATIM

Here are some story sublist selection examples.


      2	   The newest two stories.

     -2	   The oldest two stories.

     =2	   The newest two stories in chronological order.
	   (Normal order is reverse chronological order.)

    =-2	   The oldest two stories in chronological order.

     F2	   The first few lines of each of the two newest stories.

    *:5	   The oldest story through the 5th newest story.

    5:2	   The 2nd newest story through the 5th newest in
	   chronological order.

   =2:5	   Same as 5:2.

    2:2	   The only way to get just the 2nd newest story.

  -2:-5	   The 2nd oldest story through the 5th oldest.

      =	   All the stories in chronological order.

------------
.END

.IF LINES < 18 THEN SKIP TO COLUMN 1
.SEC GETTING FILE AND SPOOLER OUTPUT


If you end your story selection line with a linefeed, you
will then be asked:
.BEGIN VERBATIM

	Direct the news where? (Tty, Spooler, and/or File).

.END CONTINUE
Your response to this question should be any combination of the
letters T, S, and F, in any order, with or without any intervening
delimiters, and followed by a carriage return.  If you simply type
carriage return, then nothing will be done with the stories that were
selected, and you will be asked for another keyword expression.  If
you ask APE to save the stories in a file, you will be asked for a
file name without an extension; the extension .AP will be used on
your file.  APE will make sure the file you specify does not already
exist on your area before the stories are filed in it.  If you ask for
the stories to be spooled but not saved in a file, APE will create a
file with a name like $NEWS0.AP, which will be spooled and then
deleted.
.SKIP TO COLUMN 1
.SEC SPECIAL FEATURES
.TURN ON "%" FOR "#"

1.%In addition to normal English keywords, there are two special
forms that can be used as keywords in expressions.  The first
consists of a period (.) followed by an unsigned integer, eg., ".18";
if k is the integer following the period, this form represents the
set of the newest k stories that have come in.  The second special
form consists of a number sign (#) followed by an unsigned integer;
this form represents all the stories that have the given integer as
their AP sequence number.  This feature is especially useful for
reading the AP news digests because they are not categorized at all.
The only way to get them is to use one of the special forms.
(Actually, stories #1, #2, #201 and #202 are the ones not
categorized; occassionally the digest has some other sequence number
so it gets categorized.)  Here are some examples of keyword expressions
using these special forms.
.BEGIN VERBATIM

		CHESS * .10	     Among the last 10  stories  that
				     have  come  in,  all  those that
				     mention CHESS.

		#2 + #202	     All stories with either of these
				     sequence numbers. (These are the
				     usual  sequence  numbers  of the
				     news digests.)
.END

2.%The null keyword expression (that is, typing just CARRIAGE
RETURN without any keywords) has a special value: the set of stories
corresponding to the last keyword expression you typed.  These
stories constitute your CURRENT STORY LIST.  With this feature you
can get back a second time the stories you just looked at.  In fact,
this feature can be used consecutively any number of times, giving
the same stories every time.

3.%Typing ALTMODE in place of a keyword expression will cause
the last sublist of stories you selected to be automatically selected
again; and you will be asked where you want those stories to go.  This
feature does not disturb your current story list from which you
selected some or all as a sublist.  And again, this feature can be
used over and over again, giving the same sublist of stories each
time.

4.%A keyword expression may be continued over several lines.
Simply type a LINEFEED anywhere except in the middle of a word and
APE will type a carriage return and a colon (:) and wait for you to
type in more of the expression.

5.%Your current story list can be modified without typing
again the keywords you used to get it.  If a keyword expression
starts with +, -, or *, the missing (first) operand is taken to be
your current story list.  For example, if you have typed in "NIXON"
as your last keyword expression, you can type in "*VIETNAM" as your
next expression and you will get only stories that mention both NIXON
and VIETNAM.

6.%When stories are typed out or written in a file, a row of
stars (*'s) is placed between stories.  Note that corrections and
additions to a story are considered part of that story; thus they
will not be separated from it by a row of stars.

7.%If you type ↑O ([ESC] O on Stanford displays) during
typeout of a story, the typeout will be stopped (as usual), but will
start up again with the next story (if any).

8.%If you type ↑C and then the system REEnter command, APE
will be back to asking for keywords, and your current story list and
your current sublist will not have been changed.  (That is, you can
get either of them by typing just carriage return or altmode
respectively.  See above for those special features.)  The same
effect can be gotten on Stanford displays by typing merely [ESC] I.

9.%Upper and lower case characters are always equivalent.


.GROUP
.SEC NOTES
First, the news is kept in a fixed size file.  This means that
occasionally an old story must be deleted to make room for a new one.
If this happens after you start APE, and if you attempt to read such
a deleted story, then you will get a message something like
"1%OF%THE STORIES WENT AWAY--SORRY".
.TURN OFF

Finally, news that comes in after you start APE cannot be retrieved.
If you want to update APE's data to include the latest stories, type
↑C and then the system START command.  (When you do this your current
story list and your current sublist will be re-initialized to null.)