Business Assistant/Business Assistant.iso/stock/ibmdisk5/smhdinp3.hlp

Text File | 1992-02-08 | 9KB | 178 lines

SPECIFICATION OF ASCII FILE FORMAT-HISTORICAL DATA  SM3.02   PAGE 1 OF 8

The data to be "imported" must be in ASCII (say "askee") format, because
this is a universal format which can be understood by most communica-
tions, spreadsheet and database programs.  ASCII is a standard which
describes the bit patterns used for computer storage of individual let-
ters, digits, puncutation and other special characters.  For example the
capital letter "A" has the bit pattern 01000001.  Most personal compu-
ters can recognize ASCII.  Textual information, such as what you are
reading now, is usually stored in ASCII format.

Numbers must be in a binary format before they can be used in calcula-
tions by a computer.  The Stock Charting System stores volume, prices,
dates and other information in a binary format.  Therefore, numbers in
ASCII must be "translated" to binary before they are can be used in
calculations.

This program looks for and processes only those individual lines in the
ASCII input file which contain valid data.  Any lines which contain col-
umn headings, explanatory information, advertising, communications pro-
tocol and other things will be ignored.


SPECIFICATION OF ASCII FILE FORMAT FOR HISTORICAL DATA       PAGE 2 OF 8

WARNING: for the IMPORT function, you must have a SEPARATE file for EACH
stock for which HISTORICAL price data is to be "imported".  This differs
from importing CURRENT data, where you use only one ASCII file.

All data in the ASCII input file MUST pertain to the SAME stock.  There
is no provision to "import" historical information for many dates for
many stocks all at once - historical data for only one stock can be im-
ported at a time.  To "import" data for many stocks for just the CURRENT
date, invoke the (W) or (D) function from the Master Menu screen.

The lines in the ASCII input file can be in any order.  You can "import"
into either a daily- or weekly-updated file.  The process will not over-
write existing data and will not fill in empty "gaps" where data is mis-
sing.  It will automatically add new dates to the file as required, and
can be used to fill in a file that has just been initialized from the
Stock Select screen.





SPECIFICATION OF ASCII FILE FORMAT FOR HISTORICAL DATA       PAGE 3 OF 8

The program scans each individual line from left to right and looks for
valid data items.  These include the date, volume and high, low and
closing prices.  If the required data items are found they are converted
to binary format.  The date must be present and must match a previously
computed date on the price history file.  Number values are checked for
"reasonableness" and for proper relationship, for example high or ask >=
closing price >= low or bid.  (The >= symbol means "greater than or
equal to".)  Any error will cause that line to be discarded.

Data items must be separated by blank spaces or other non-numeric charac-
ters.  Either fractional or decimal values are acceptable.  Fractions
must be separated from their corresponding whole numbers by one and only
one blank space.

The program will ignore characters such as * to indicate ex-dividend.
It will also ignore any quote marks or commas that may be used to separ-
ate data items.  Thus, it will accept data in the CSV (comma-separated
value) format used by some database programs.  It is the responsibility
of the user, in the process of using the external communications or
other program, to make sure the required data items are available.

SPECIFICATION OF ASCII FILE FORMAT FOR HISTORICAL DATA       PAGE 4 OF 8

Here are some examples of acceptable data arranged by trading period
date, high, low, close and volume:

    01/29/88   *120        109 3/4    110 1/2   110375   (* ignored)
    "01/29/88",15.25,14,14.875,56259  (CSV format)
    01-29-88  31.125 29 30.5 4075     (either - or / in date is OK)

For the above data format, you would type MABCV to specify the order in
which these data items appear.

The program will ask you to specify the sequence in which data items
appear in the file you are "importing" into the Stock Charting System.
This sequence may vary, depending on what source the data comes from.
The required data items must be in the same sequence on each line on
which they appear.






SPECIFICATION OF ASCII FILE FORMAT FOR HISTORICAL DATA       PAGE 5 OF 8

Each required data item is identified by a letter of the alphabet, such
as A for ask or high, B for bid or low, etc.  The sequence in which data
items appear in the input is specified by typing those letters in a cor-
responding sequence, for example MABCV for date-high-low-close-volume.
If you don't know the sequence, you can find out from the documentation
for the program that created the file, or by visual inspection after
displaying the file on the screen or printer.  Usually a program that
creates a file can also display it.

Note there are several different allowable date formats.  Use M for a
date in mm/dd/yy or mm-dd-yy format (generally used in the USA).  Use D
for a date in dd/mm/yy or dd-mm-yy format; or use Y for a date in
yy/mm/dd or yy-mm-dd format.  The program will also accept dates without
punctuation or with 4-digit years, for example 112588 or 19881125.
Dates without punctuation must be exactly six or exactly eight digits
long.





SPECIFICATION OF ASCII FILE FORMAT FOR HISTORICAL DATA       PAGE 6 OF 8

To skip over a data item you don't want to use, type the letter "R" if
it is a stock price (ask/bid/last/open/etc.); otherwise type the letter
"S".  In general you can use "S" to skip any data item, UNLESS it may
contain a number with a fractional value such as 2 11/16.  "S" skips
anything delimited by spaces or double quotes, so it won't work with
fractions.  That's why you have to use "R" to consistently skip over
numeric values that may contain fractions.  Either "R" or "S" will work
with whole numbers and decimal values.

For example, when receiving historical quotes from Dow Jones Information
Services, the data items are in date-high-low-close-volume order.  There-
fore, if you want only the date and closing price, type the letters MRRC
to specify the data item order.  Note in this case you do not have to
specify the volume if you don't want; the program will ignore it.

Use S instead of R to skip a field such as the time of day or a date.

Use V for volume in hundreds (the normal case).  Otherwise use U.  Which
one to use can be determined by inspection of the data.  U means volume
in UNITS of 1.

SPECIFICATION OF ASCII FILE FORMAT FOR HISTORICAL DATA       PAGE 7 OF 8

Not all of the aforementioned data items must be present.  The program
can use the trading period date and the current volume, high, low and
close.  However the only items that absolutely must be available on each
line are the date and either the current closing price (or net asset
value) or the ask and bid prices.  If the ask and bid prices are pres-
ent, but not the closing price, the closing price is set to the bid
price.  If only the closing price is present, the high and low are set
equal to the close.

After the "translation" process is finished, you are automatically
returned to the Data Entry screen.  The file should be inspected to make
sure the imported data got through.  In addition you must manually enter
holidays into daily-updated files, by selecting the appropriate dates
and typing E and then Y.  Any dates without data filled in and not
marked as holidays will interrupt moving average calculations.

The program does not indicate errors in the incoming data during the
translation process; invalid data is simply ignored.  Errors will become
apparent as you inspect the data - where errors were found, the data
will be missing from the price history file.

SPECIFICATION OF ASCII FILE FORMAT FOR HISTORICAL DATA       PAGE 8 OF 8

If you got most of the data but a few lines are missing, the problem
could be "glitches" on the telephone line (when receiving data through a
modem).  This could cause some "garbage" to get i