* The square root radical sign surrounding b is rendered as b^-2
- * metavariable subscripts are simply appended to their metavariables.
+ * |a| is used to render the absolute-value operation.
* `x' between digits is used to render the multiplication sign.
compound-AND example was incorrectly lowercased. In item 1 of the BEGIN
explanation, the word `statement' was incorrectly uppercased.
+Notes:
+
+ * Tags [See *1], [See *2], etc, are not part of the original; they reference
+ footnotes following the transcript.
+
+ * Tags such as [See 5-8] are not part of the original, they reference other
+ quotes from the text given below by page number.
+
Otherwise, the appendix F transcription is exact, even down to hyphen breaks
-and spacing.
+and spacing (allowing for the fact that the original typewriter spacing was
+somewhat irregular...).
+
+The combination of Appendix F and the notes includes essentially all the
+manual's documentation of the CORC language itself. Most of the text is
+tutorials and exercises.
This implementation preserves the CORC-62 distinction between LOG and LN,
contrary to the transcript below which describes CORC-63 (which identifies
transcribed from the manual. We include every complete program
example. The following list maps programs to original page numbers:
+simplecorc.corc -- 4-6
+gasbill.corc -- 4-9
+hearts.corc -- 4-10
sumsquares.corc -- 5-4
-power.corc -- 5-6
+powercorc.corc -- 5-6
factorial.corc -- 5-6
-quadratic.corc -- 5-9
-title.corc -- 7-3
+quadcorc.corc -- 5-9
+title.corc -- 7-3 (note: this one uses continuations)
-We have supplied leading comments for these programs; they are otherwise
-unaltered.
+We have supplied leading comments and test data for these programs;
+they are otherwise unaltered.
---------------------------------- CUT HERE ----------------------------------
once in label field.
Block label used for only one set of BEGIN-END statements.
e. Variables must be listed in Dictionary. If no initial value
- is given zero is assumed.
+ is given zero is assumed. [See *1]
f. One or two subscripts, enclosed in parentheses. May be
any expression (including subscripted variables) whose
value at execution is a positive integer not greater than
- the maximum declared for this variable in Dictionary.
+ the maximum declared for this variable in Dictionary. [See D-2]
In Dictionary and Input Data subscripts given as integers in
- subscript field; parentheses are not used.
+ subscript field; parentheses are not used. [See *1]
\f
Arithmetic Operators
--------------------
Initially right digit should be zero on all cards to leave
room for later additions.
- Program Arrangement
+ Program Arrangement [See *1]
-------------------
Arrange and number programming forms in the following order:
1. Preliminary Description
- 2. Dictionary
+ 2. Dictionary [See 2-10]
List all variables to be used
Specify initial values if not zero
Specify maximum value for each subscript.
with value of expression assigned to
variable v. Three expressions on list
enclosed in parentheses mean from h to k
- in steps of k.
+ in steps of k. [See 5-8]
Communication Statements
------------------------
notes only.
---------------------------------- CUT HERE ----------------------------------
+
+[*1] This implementation of CORC does not support or allow a
+Dictionary section. Instead, variable initializations must be done via
+CUPL-style DATA and ALLOCATE statements.
+
+[*2] Ignore this section. Program statements are free-format, with
+continuations not supported (though the example program
+test/title.corc shows the syntax, it will break cupl). Data for read
+statements is accepted in CUPL format following the keyword *DATA.
+
+For completeness, however, the Dictionary feature is documented here.
+
+From 2-10:
+
+Dictionary of Variables
+-----------------------
+ In addition to a set of statements CORC requires a pro-
+gram to contain another part known as the Dictionary. The Diction-
+ary of a program is merely a list of all the variables used in
+the program. along with, if desired, the initial assigned values of
+the variables. If no initial value is specified the computer
+assigns the initial value zero.
+
+From 2-11:
+
+ In the above example the Dictionary might look like this:
+
+ A 1
+ B -1
+ C -6
+ ROOT
+ X1
+ X2
+
+[The `above example' is the simplecorc.corc program. The CORC Dictionary
+is equivalent to a CUPL DATA section, but also allowed the programmer to
+dimension array variables. The example form on 2-12 makes it clear that
+the Dictionary was distinguished from the program proper by being in a
+different lower range of card line numbers.]
+
+From 5-8:
+
+Three expressions on a list, enclosed in parentheses, are in-
+terpreted in the following way:
+ 1. The first expression gives the initial value for the vari-
+ able.
+ 2. The second expression gives the difference between con-
+ secutive values.
+ 3. The third expression indicates where to stop -- the final
+ value for the variable is less than or equal to the value
+ of the third expression.
+
+[... examples omitted ...]
+
+ More than one such "triple" may be used on a list, and
+"triples" may be intermixed with separate expressions;
+
+From 6-5:
+
+ A particular variable either has no subscripts, one sub-
+script, or two subscripts and this use must be consistent through-
+out a program. A variable cannot appear as X(I) in one statement
+and X(I, J) or just X in another statement of the same program.
+The nature of a variable (whether it is to be subscripted or not)
+must be indicated when the variable is listed in the CORC Diction-
+ary. This is done by giving the maximum value of any subscripts
+that will be used in columns 21-25 of the Dictionary form. If no
+subscripts will be used these columns will be left blank in the
+line for that variable. If one subscript is to be used, the maxi-
+mum value that that subscript will take on anywhere in the pro-
+gram must be given in columns 21-23; columns 24-25 are left blank.
+(Note that this is the maximum value of the subscript, and not
+the maximum value of the variable.) If two subscripts are to be
+used the maximum value of the first is given in columns 21-23
+and the maximum value of the second in columns 24-25. For ex-
+ample, if the Dicitonary [sic] looks like the following:
+
+ SCALAR
+ VECTOR 45
+ MATRIX 100 2
+ ARRAY 3 32
+
+then SCALAR is a simple variable that will not have any sub-
+scripts anywhere in the program. VECTOR will have one subscript
+everwhere it appears in the program [...] MATRIX [...] will
+appear each time with two subscripts [...] ARRAY will also
+always have two subscripts; [...]
+
+From D-2:
+
+Automatic Integer Round-off
+---------------------------
+a. The value of a subscript is rounded off to the nearest
+ integer.
+b. If the round-off involves a change of greater than
+ 10^-9 (approximately; the number is subject to some
+ variation) an error message is given.
+
+From D-3:
+
+Automatic Relative Round-off for x r y
+--------------------------------------
+a. If both x and y are zero the condition is applied as it stands.
+b. If either x or y is not zero:
+ (i) Both x and y are multiplied by MAX(|x|, |y|);
+ (ii) The results are rounded off to the nearest
+ integer if this involves a change of less
+ than 10^-9 (10^-7 for the Burroughs 220), but
+ not otherwise;
+ (iii) The specified condition is interpreted for
+ the resulting numbers.
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