man/man1/rcalc.1

.\" RCSid "$Id: rcalc.1,v 1.16 2022/03/11 22:50:13 greg Exp $"
.TH RCALC 1 4/6/99 RADIANCE
.SH NAME
rcalc - record calculator
.SH SYNOPSIS
.B rcalc
[
.B \-b
][
.B \-l
][
.B "\-p | \-P"
][
.B \-n
][
.B \-w
][
.B \-u
][
.B \-tS
][
.B "\-i format"
][
.B "\-o format"
][
.B "\-in M"
][
.B "\-on M"
][
.B "\-f source"
][
.B "\-e expr"
][
.B "\-s svar=sval"
]
file ..
.SH DESCRIPTION
.I Rcalc
transforms ``records'' from each
.I file
according to the given set of literal and relational information.
By default, records are separated by newlines, and contain
numeric fields separated by tabs.
The
.I \-tS
option is used to specify an alternate tab character.
.PP
A
.I \-i format
option specifies a template for an alternate
input record format.
.I Format
is interpreted as a specification string if it contains a dollar sign '$'.
Otherwise, it is interpreted as the name of the file containing
the format specification.
In either case, if the format does not end with a newline, one will be added
automatically.
A special form of the
.I \-i
option may be followed immediately by a 'd' or an 'f' and an optional
count, which defaults to 1, indicating the number of double or float
binary values to read per record on the input file.
If the input is byte-swapped, the
.I \-iD
or
.I \-iF
options may be substituted.
If binary input is specified, no format string or file is needed.
.PP
A
.I \-o format
option specifies an alternate output record format.
It is interpreted the same as an input specification, except that
the special
.I \-od
or
.I \-of
options do not require a count, as this will be determined by the
number of output channels in the given expressions.
If byte-swapped output is desired, the
.I \-oD
or
.I \-oF
options may be substituted.
.PP
The
.I \-p
option specifies "passive mode," where characters that do not
match the input format are passed unaltered to the output.
If the
.I \-P
option is given instead, then valid input records that do not
yield a positive
.I cond
value are similarly passed to the output.
(See paragraph below.)\0
These options options require that the
.I \-i
input format and
.I \-o
output format also be present.
With both input and output formats, the passive mode can
effectively substitute information in the middle of a file
or stream without affecting the rest of the data.
.PP
If a
.I \-in
option is given with a positive integer argument,
.I rcalc
will stop processing input once it has loaded this number of records.
Similarly, if a
.I \-on
option is present,
.I rcalc
will stop after producing this many records, which may be a smaller
number if the
.I cond
variable is used.
If multiple input files are given, these counts are continuous over
the input and do not reset on each file.
.PP
The variable and function definitions in each
.I \-f source
file are read and compiled from the RADIANCE library where it is found.
The
.I \-e expr
option can be used to define variables on the command line.
Since many of the characters in an expression have special meaning
to the shell, it should usually be enclosed in single quotes.
The
.I \-s svar=sval
option can be used to assign a string variable a string value.
If this string variable appears in an input format, only records
with the specified value will be processed.
.PP
The
.I \-b
option instructs the program to accept only exact matches.
By default, tabs and spaces are ignored except
as field separators.
The
.I \-l
option instructs the program to ignore newlines in the input,
basically treating them the same as tabs and spaces.
Normally, the beginning of the input format matches the beginning of
a line, and the end of the format matches the end of a line.
With the
.I \-l
option, the input format can match anywhere on a line.
.PP
The
.I \-w
option causes non-fatal error messages (such as division by zero) to
be supressed.
The
.I \-u
option causes output to be flushed after each record.
The
.I \-n
option tells the program not to get any input, but to produce a
single output record.
Otherwise, if no files are given, the standard input is read.
.PP
Format files associate names with string and numeric fields
separated by literal information in a record.
A numeric field is given in a format file as a dollar sign, followed
by curly braces enclosing a variable name:
.PP
        This is a numeric field: ${vname}
.PP
A string variable is enclosed in parentheses:
.PP
        This is a string field: $(sname)
.PP
The program attempts to match literal information in
the input format to its input and assign string and numeric
fields accordingly.
If a string or numeric field variable appears more than once in
the input format, input values for the corresponding fields must
match (ie. have the same value) for the whole record to match.
Numeric values are allowed some deviation, on the order of 0.1%, but
string variables must match exactly.
Thus, dummy variables for "don't care" fields should be given unique
names so that they are not all required to take on the same value.
.PP
For each valid input record, an output record is produced
in its corresponding format.
Output field widths are given implicitly by the space occupied
in the format file, including the dollar sign and braces.
This makes it impossible to produce fields with fewer than four
characters.
If the
.I \-b
option is specified, input records must exactly match the
template.
By default, the character following each input field is used as
a delimiter.
This implies that string fields that are followed by white space
cannot contain strings with white space.
Also, numeric fields followed but not preceded by white space
will not accept numbers preceded by white space.
Adjacent input fields are advisable only with the
.I \-b
option.
Numeric output fields may contain expressions as well as variables.
A dollar sign may appear in a literal as two dollar signs ($$).
.PP
The definitions specified in
.I \-e
and
.I \-f
options relate numeric output fields to numeric input fields.
For the default record format, a field is a variable of the form
$N, where N is the column number, beginning with 1.
Output columns appear on the left-hand side of assignments, input
columns appear on the right-hand side.
.PP
A variable definition has the form:
.PP

        var = expression ;

.PP
Any instance of the variable in an expression will be replaced
with its definition.
.PP
An expression contains real numbers, variable names, function calls,
and the following operators:
.PP
        +  -  *  /  ^
.PP
Operators are evaluated left to right, except '^',
which is right associative.
Powers have the highest precedence; multiplication and
division are evaluated before addition and subtraction.
Expressions can be grouped with parentheses.
All values are double precision real.
.PP
A function definition has the form:
.PP

        func(a1, a2, ..) = expression ;

.PP
The expression can contain instances of the function arguments
as well as other variables and functions.
Function names can be passed as arguments.
Recursive functions can be defined using calls to the defined
function or other functions calling the defined function.
.PP
The variable
.I cond,
if defined, will determine whether the current input record produces
an output record.
If
.I cond
is positive, output is produced.
If
.I cond
is less than or equal to zero, the record is skipped (or passed to the
output if
.I \-P
is specified) and no other expressions
are evaluated.
This provides a convenient method for avoiding inappropriate calculations.
The following library of pre-defined functions and variables is provided:
.TP 10n
.BR $N
Return the value for input column
.I N.
If an input format is given, using a channel number generates an error.
.TP
.BR "in(n)"
Return the value for input column
.I n,
or the number of columns available in this record if
.I n
is 0.
This is an alternate way to get a column value instead of using
the $N notation, and is more flexible since it is programmable.
This function is disabled if an input format is used.
.TP
.BR "if(test, then, else)"
if test is greater than zero,
then is evaluated, otherwise else is evaluated.
This function is necessary for recursive definitions.
.TP
.BR "select(N, a1, a2, ..)"
return aN (N is rounded to the nearest integer).
This function provides array capabilities.
If
.I N
is zero, the number of available arguments is returned.
.TP
.BR "rand(x)"
compute a random number between 0 and 1 based on x.
.TP
.BR "min(a1, a2, ..)"
return the minimum value from a list of arguments.
.TP
.BR "max(a1, a2, ..)"
return the maximum value from a list of arguments.
.TP
.BR "floor(x)"
return largest integer not greater than x.
.TP
.BR "ceil(x)"
return smallest integer not less than x.
.TP
.BR "sqrt(x)"
return square root of x.
.TP
.BR "exp(x)"
compute e to the power of x (e approx = 2.718281828).
.TP
.BR "log(x)"
compute the logarithm of x to the base e.
.TP
.BR "log10(x)"
compute the logarithm of x to the base 10.
.TP
.BR PI
the ratio of a circle's circumference to its diameter.
.TP
.BR recno
the number of records recognized thus far.
.TP
.BR outno
the number or records output thus far (including this one).
.TP
.BR "sin(x), cos(x), tan(x)"
trigonometric functions.
.TP
.BR "asin(x), acos(x), atan(x)"
inverse trigonometric functions.
.TP
.BR "atan2(y, x)"
inverse tangent of y/x (range \-pi to pi).
.SH EXAMPLE
To print the square root of column two in column one,
and column one times column three in column two:
.IP "" .2i
rcalc -e '$1=sqrt($2);$2=$1*$3' inputfile > outputfile
.SH ENVIRONMENT
RAYPATH         the directories to check for auxiliary files.
.SH AUTHOR
Greg Ward
.SH BUGS
String variables can only be used in input and output formats and
.I \-s
options, not in definitions.
.PP
Tabs count as single spaces inside fields.
.PP
The
.I \-P
option buffers up to 16 Kbytes of data per record.
Longer records passed because the "cond" variable
evaluates to <= 0 will be partial; a warning will
be generated and the string "*** MISSING DATA ***"
will appear at the break.
The only workaround is to use the
.I \-p
option instead, which does not pass rejected records.
.SH "SEE ALSO"
cnt(1), ev(1), getinfo(1), icalc(1), rcollate(1), rlam(1),
rsplit(1), tabfunc(1), total(1)
Revision:	1.17
Committed:	Sun Mar 13 16:11:48 2022 UTC (2 years, 2 months ago) by greg
Branch:	MAIN
CVS Tags:	rad5R4, HEAD
Changes since 1.16:	+12 -1 lines
Error occurred while calculating annotation data.
Log Message:	feat(rcalc): Added warning and embedded message when buffer overflows with -P
#	Content
1	.\" RCSid "$Id: rcalc.1,v 1.16 2022/03/11 22:50:13 greg Exp $"
2	.TH RCALC 1 4/6/99 RADIANCE
3	.SH NAME
4	rcalc - record calculator
5	.SH SYNOPSIS
6	.B rcalc
7	[
8	.B \-b
9	][
10	.B \-l
11	][
12	.B "\-p \| \-P"
13	][
14	.B \-n
15	][
16	.B \-w
17	][
18	.B \-u
19	][
20	.B \-tS
21	][
22	.B "\-i format"
23	][
24	.B "\-o format"
25	][
26	.B "\-in M"
27	][
28	.B "\-on M"
29	][
30	.B "\-f source"
31	][
32	.B "\-e expr"
33	][
34	.B "\-s svar=sval"
35	]
36	file ..
37	.SH DESCRIPTION
38	.I Rcalc
39	transforms ``records'' from each
40	.I file
41	according to the given set of literal and relational information.
42	By default, records are separated by newlines, and contain
43	numeric fields separated by tabs.
44	The
45	.I \-tS
46	option is used to specify an alternate tab character.
47	.PP
48	A
49	.I \-i format
50	option specifies a template for an alternate
51	input record format.
52	.I Format
53	is interpreted as a specification string if it contains a dollar sign '$'.
54	Otherwise, it is interpreted as the name of the file containing
55	the format specification.
56	In either case, if the format does not end with a newline, one will be added
57	automatically.
58	A special form of the
59	.I \-i
60	option may be followed immediately by a 'd' or an 'f' and an optional
61	count, which defaults to 1, indicating the number of double or float
62	binary values to read per record on the input file.
63	If the input is byte-swapped, the
64	.I \-iD
65	or
66	.I \-iF
67	options may be substituted.
68	If binary input is specified, no format string or file is needed.
69	.PP
70	A
71	.I \-o format
72	option specifies an alternate output record format.
73	It is interpreted the same as an input specification, except that
74	the special
75	.I \-od
76	or
77	.I \-of
78	options do not require a count, as this will be determined by the
79	number of output channels in the given expressions.
80	If byte-swapped output is desired, the
81	.I \-oD
82	or
83	.I \-oF
84	options may be substituted.
85	.PP
86	The
87	.I \-p
88	option specifies "passive mode," where characters that do not
89	match the input format are passed unaltered to the output.
90	If the
91	.I \-P
92	option is given instead, then valid input records that do not
93	yield a positive
94	.I cond
95	value are similarly passed to the output.
96	(See paragraph below.)\0
97	These options options require that the
98	.I \-i
99	input format and
100	.I \-o
101	output format also be present.
102	With both input and output formats, the passive mode can
103	effectively substitute information in the middle of a file
104	or stream without affecting the rest of the data.
105	.PP
106	If a
107	.I \-in
108	option is given with a positive integer argument,
109	.I rcalc
110	will stop processing input once it has loaded this number of records.
111	Similarly, if a
112	.I \-on
113	option is present,
114	.I rcalc
115	will stop after producing this many records, which may be a smaller
116	number if the
117	.I cond
118	variable is used.
119	If multiple input files are given, these counts are continuous over
120	the input and do not reset on each file.
121	.PP
122	The variable and function definitions in each
123	.I \-f source
124	file are read and compiled from the RADIANCE library where it is found.
125	The
126	.I \-e expr
127	option can be used to define variables on the command line.
128	Since many of the characters in an expression have special meaning
129	to the shell, it should usually be enclosed in single quotes.
130	The
131	.I \-s svar=sval
132	option can be used to assign a string variable a string value.
133	If this string variable appears in an input format, only records
134	with the specified value will be processed.
135	.PP
136	The
137	.I \-b
138	option instructs the program to accept only exact matches.
139	By default, tabs and spaces are ignored except
140	as field separators.
141	The
142	.I \-l
143	option instructs the program to ignore newlines in the input,
144	basically treating them the same as tabs and spaces.
145	Normally, the beginning of the input format matches the beginning of
146	a line, and the end of the format matches the end of a line.
147	With the
148	.I \-l
149	option, the input format can match anywhere on a line.
150	.PP
151	The
152	.I \-w
153	option causes non-fatal error messages (such as division by zero) to
154	be supressed.
155	The
156	.I \-u
157	option causes output to be flushed after each record.
158	The
159	.I \-n
160	option tells the program not to get any input, but to produce a
161	single output record.
162	Otherwise, if no files are given, the standard input is read.
163	.PP
164	Format files associate names with string and numeric fields
165	separated by literal information in a record.
166	A numeric field is given in a format file as a dollar sign, followed
167	by curly braces enclosing a variable name:
168	.PP
169	This is a numeric field: ${vname}
170	.PP
171	A string variable is enclosed in parentheses:
172	.PP
173	This is a string field: $(sname)
174	.PP
175	The program attempts to match literal information in
176	the input format to its input and assign string and numeric
177	fields accordingly.
178	If a string or numeric field variable appears more than once in
179	the input format, input values for the corresponding fields must
180	match (ie. have the same value) for the whole record to match.
181	Numeric values are allowed some deviation, on the order of 0.1%, but
182	string variables must match exactly.
183	Thus, dummy variables for "don't care" fields should be given unique
184	names so that they are not all required to take on the same value.
185	.PP
186	For each valid input record, an output record is produced
187	in its corresponding format.
188	Output field widths are given implicitly by the space occupied
189	in the format file, including the dollar sign and braces.
190	This makes it impossible to produce fields with fewer than four
191	characters.
192	If the
193	.I \-b
194	option is specified, input records must exactly match the
195	template.
196	By default, the character following each input field is used as
197	a delimiter.
198	This implies that string fields that are followed by white space
199	cannot contain strings with white space.
200	Also, numeric fields followed but not preceded by white space
201	will not accept numbers preceded by white space.
202	Adjacent input fields are advisable only with the
203	.I \-b
204	option.
205	Numeric output fields may contain expressions as well as variables.
206	A dollar sign may appear in a literal as two dollar signs ($$).
207	.PP
208	The definitions specified in
209	.I \-e
210	and
211	.I \-f
212	options relate numeric output fields to numeric input fields.
213	For the default record format, a field is a variable of the form
214	$N, where N is the column number, beginning with 1.
215	Output columns appear on the left-hand side of assignments, input
216	columns appear on the right-hand side.
217	.PP
218	A variable definition has the form:
219	.PP
220
221	var = expression ;
222
223	.PP
224	Any instance of the variable in an expression will be replaced
225	with its definition.
226	.PP
227	An expression contains real numbers, variable names, function calls,
228	and the following operators:
229	.PP
230	+ - * / ^
231	.PP
232	Operators are evaluated left to right, except '^',
233	which is right associative.
234	Powers have the highest precedence; multiplication and
235	division are evaluated before addition and subtraction.
236	Expressions can be grouped with parentheses.
237	All values are double precision real.
238	.PP
239	A function definition has the form:
240	.PP
241
242	func(a1, a2, ..) = expression ;
243
244	.PP
245	The expression can contain instances of the function arguments
246	as well as other variables and functions.
247	Function names can be passed as arguments.
248	Recursive functions can be defined using calls to the defined
249	function or other functions calling the defined function.
250	.PP
251	The variable
252	.I cond,
253	if defined, will determine whether the current input record produces
254	an output record.
255	If
256	.I cond
257	is positive, output is produced.
258	If
259	.I cond
260	is less than or equal to zero, the record is skipped (or passed to the
261	output if
262	.I \-P
263	is specified) and no other expressions
264	are evaluated.
265	This provides a convenient method for avoiding inappropriate calculations.
266	The following library of pre-defined functions and variables is provided:
267	.TP 10n
268	.BR $N
269	Return the value for input column
270	.I N.
271	If an input format is given, using a channel number generates an error.
272	.TP
273	.BR "in(n)"
274	Return the value for input column
275	.I n,
276	or the number of columns available in this record if
277	.I n
278	is 0.
279	This is an alternate way to get a column value instead of using
280	the $N notation, and is more flexible since it is programmable.
281	This function is disabled if an input format is used.
282	.TP
283	.BR "if(test, then, else)"
284	if test is greater than zero,
285	then is evaluated, otherwise else is evaluated.
286	This function is necessary for recursive definitions.
287	.TP
288	.BR "select(N, a1, a2, ..)"
289	return aN (N is rounded to the nearest integer).
290	This function provides array capabilities.
291	If
292	.I N
293	is zero, the number of available arguments is returned.
294	.TP
295	.BR "rand(x)"
296	compute a random number between 0 and 1 based on x.
297	.TP
298	.BR "min(a1, a2, ..)"
299	return the minimum value from a list of arguments.
300	.TP
301	.BR "max(a1, a2, ..)"
302	return the maximum value from a list of arguments.
303	.TP
304	.BR "floor(x)"
305	return largest integer not greater than x.
306	.TP
307	.BR "ceil(x)"
308	return smallest integer not less than x.
309	.TP
310	.BR "sqrt(x)"
311	return square root of x.
312	.TP
313	.BR "exp(x)"
314	compute e to the power of x (e approx = 2.718281828).
315	.TP
316	.BR "log(x)"
317	compute the logarithm of x to the base e.
318	.TP
319	.BR "log10(x)"
320	compute the logarithm of x to the base 10.
321	.TP
322	.BR PI
323	the ratio of a circle's circumference to its diameter.
324	.TP
325	.BR recno
326	the number of records recognized thus far.
327	.TP
328	.BR outno
329	the number or records output thus far (including this one).
330	.TP
331	.BR "sin(x), cos(x), tan(x)"
332	trigonometric functions.
333	.TP
334	.BR "asin(x), acos(x), atan(x)"
335	inverse trigonometric functions.
336	.TP
337	.BR "atan2(y, x)"
338	inverse tangent of y/x (range \-pi to pi).
339	.SH EXAMPLE
340	To print the square root of column two in column one,
341	and column one times column three in column two:
342	.IP "" .2i
343	rcalc -e '$1=sqrt($2);$2=$1*$3' inputfile > outputfile
344	.SH ENVIRONMENT
345	RAYPATH the directories to check for auxiliary files.
346	.SH AUTHOR
347	Greg Ward
348	.SH BUGS
349	String variables can only be used in input and output formats and
350	.I \-s
351	options, not in definitions.
352	.PP
353	Tabs count as single spaces inside fields.
354	.PP
355	The
356	.I \-P
357	option buffers up to 16 Kbytes of data per record.
358	Longer records passed because the "cond" variable
359	evaluates to <= 0 will be partial; a warning will
360	be generated and the string "* MISSING DATA *"
361	will appear at the break.
362	The only workaround is to use the
363	.I \-p
364	option instead, which does not pass rejected records.
365	.SH "SEE ALSO"
366	cnt(1), ev(1), getinfo(1), icalc(1), rcollate(1), rlam(1),
367	rsplit(1), tabfunc(1), total(1)