Patch attached and applied. Thanks.
I adjusted the oid so prevent a duplicate, and adjusted the regression
test to remove comments on now non-existant functions.
I also tested the output and it looks good:
test=> select numeric_fac(10);
numeric_fac
-------------
3628800
(1 row)
test=> select numeric_fac(1);
numeric_fac
-------------
1
(1 row)
test=> select numeric_fac(2);
numeric_fac
-------------
2
(1 row)
test=> select numeric_fac(4);
numeric_fac
-------------
24
(1 row)
test=> select numeric_fac(3);
numeric_fac
-------------
6
(1 row)
I will check the docs now.
---------------------------------------------------------------------------
Gavin Sherry wrote:
> Attached is a patch implementing factorial(), returning numeric. Points to
> note:
>
> 1) arttype is numeric. I thought this was the best way of allowing
> arbitarily large factorials, even though factorial(2^63) is a large
> number. Happy to change to integers if this is overkill.
> 2) since we're accepting numeric arguments, the patch tests for floats. If
> a numeric is passed with non-zero decimal portion, an error is raised
> since (from memory) they are undefined.
> 3) I have not removed factorial([int2|int4|int8]), not their operator
> counterparts since I didn't know what people would want done with these.
> 4) I haven't added any documentation but am happy to once I know if people
> want int or numeric arguments.
> Attached is a revised patch based on your Tom's comments. It removes
> int[248]fac(), modifies regression tests (which referenced int4fac()),
> and implements a much cleaned numeric_fac().
--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073
Index: src/backend/utils/adt/int.c
===================================================================
RCS file: /cvsroot/pgsql-server/src/backend/utils/adt/int.c,v
retrieving revision 1.58
diff -c -c -r1.58 int.c
*** src/backend/utils/adt/int.c 29 Nov 2003 19:51:58 -0000 1.58
--- src/backend/utils/adt/int.c 1 Dec 2003 21:30:41 -0000
***************
*** 26,32 ****
* intpl, intmi, int4mul, intdiv
*
* Arithmetic operators:
! * intmod, int4fac
*/
#include "postgres.h"
--- 26,32 ----
* intpl, intmi, int4mul, intdiv
*
* Arithmetic operators:
! * intmod
*/
#include "postgres.h"
***************
*** 849,888 ****
PG_RETURN_INT32(arg1 % arg2);
}
- /* int[24]fac()
- * Factorial
- */
- Datum
- int4fac(PG_FUNCTION_ARGS)
- {
- int32 arg1 = PG_GETARG_INT32(0);
- int32 result;
-
- if (arg1 == 0)
- result = 1;
- else if (arg1 < 0)
- result = 0;
- else
- for (result = 1; arg1 > 0; --arg1)
- result *= arg1;
- PG_RETURN_INT32(result);
- }
-
- Datum
- int2fac(PG_FUNCTION_ARGS)
- {
- int16 arg1 = PG_GETARG_INT16(0);
- int32 result;
-
- if (arg1 == 0)
- result = 1;
- else if (arg1 < 0)
- result = 0;
- else
- for (result = 1; arg1 > 0; --arg1)
- result *= arg1;
- PG_RETURN_INT32(result);
- }
/* int[24]abs()
* Absolute value
--- 849,854 ----
Index: src/backend/utils/adt/int8.c
===================================================================
RCS file: /cvsroot/pgsql-server/src/backend/utils/adt/int8.c,v
retrieving revision 1.49
diff -c -c -r1.49 int8.c
*** src/backend/utils/adt/int8.c 29 Nov 2003 19:51:58 -0000 1.49
--- src/backend/utils/adt/int8.c 1 Dec 2003 21:30:41 -0000
***************
*** 561,586 ****
PG_RETURN_INT64(result);
}
- /* int8fac()
- * Factorial
- */
- Datum
- int8fac(PG_FUNCTION_ARGS)
- {
- int64 arg1 = PG_GETARG_INT64(0);
- int64 result;
- int64 i;
-
- if (arg1 == 0)
- result = 1;
- else if (arg1 < 1)
- result = 0;
- else
- for (i = arg1, result = 1; i > 0; --i)
- result *= i;
-
- PG_RETURN_INT64(result);
- }
Datum
int8inc(PG_FUNCTION_ARGS)
--- 561,566 ----
Index: src/backend/utils/adt/numeric.c
===================================================================
RCS file: /cvsroot/pgsql-server/src/backend/utils/adt/numeric.c,v
retrieving revision 1.68
diff -c -c -r1.68 numeric.c
*** src/backend/utils/adt/numeric.c 29 Nov 2003 19:51:59 -0000 1.68
--- src/backend/utils/adt/numeric.c 1 Dec 2003 21:30:45 -0000
***************
*** 1288,1293 ****
--- 1288,1342 ----
* ----------------------------------------------------------------------
*/
+ /*
+ * numeric_fac()
+ * Computer factorial
+ */
+
+ Datum
+ numeric_fac(PG_FUNCTION_ARGS)
+ {
+
+ int64 num = PG_GETARG_INT64(0);
+ NumericVar count;
+ NumericVar fact;
+ NumericVar zerovar;
+ NumericVar result;
+ Numeric res;
+
+ if(num < 1) {
+ res = make_result(&const_one);
+ PG_RETURN_NUMERIC(res);
+ }
+
+
+ init_var(&fact);
+ init_var(&count);
+ init_var(&result);
+ init_var(&zerovar);
+ zero_var(&zerovar);
+
+ int8_to_numericvar((int64)num, &result);
+ set_var_from_var(&const_one, &count);
+
+ for(num = num - 1; num > 0; num--) {
+ set_var_from_var(&result,&count);
+
+ int8_to_numericvar((int64)num,&fact);
+
+ mul_var(&count, &fact, &result, count.dscale + fact.dscale);
+ }
+
+ res = make_result(&count);
+
+ free_var(&count);
+ free_var(&fact);
+ free_var(&result);
+ free_var(&zerovar);
+
+ PG_RETURN_NUMERIC(res);
+ }
+
/*
* numeric_sqrt() -
Index: src/include/catalog/pg_operator.h
===================================================================
RCS file: /cvsroot/pgsql-server/src/include/catalog/pg_operator.h,v
retrieving revision 1.122
diff -c -c -r1.122 pg_operator.h
*** src/include/catalog/pg_operator.h 29 Nov 2003 22:40:58 -0000 1.122
--- src/include/catalog/pg_operator.h 1 Dec 2003 21:30:48 -0000
***************
*** 122,133 ****
DATA(insert OID = 352 ( "=" PGNSP PGUID b t 28 28 16 352 0 0 0 0 0 xideq eqsel
eqjoinsel));
DATA(insert OID = 353 ( "=" PGNSP PGUID b f 28 23 16 0 0 0 0 0 0 xideqint4
eqseleqjoinsel ));
DATA(insert OID = 385 ( "=" PGNSP PGUID b t 29 29 16 385 0 0 0 0 0 cideq eqsel
eqjoinsel));
DATA(insert OID = 386 ( "=" PGNSP PGUID b t 22 22 16 386 0 0 0 0 0 int2vectoreq
eqseleqjoinsel ));
DATA(insert OID = 387 ( "=" PGNSP PGUID b f 27 27 16 387 0 0 0 0 0 tideq eqsel
eqjoinsel));
#define TIDEqualOperator 387
- DATA(insert OID = 388 ( "!" PGNSP PGUID r f 20 0 20 0 0 0 0 0 0 int8fac - -
));
- DATA(insert OID = 389 ( "!!" PGNSP PGUID l f 0 20 20 0 0 0 0 0 0 int8fac - -
));
DATA(insert OID = 410 ( "=" PGNSP PGUID b t 20 20 16 410 411 412 412 412 413 int8eq eqsel
eqjoinsel));
DATA(insert OID = 411 ( "<>" PGNSP PGUID b f 20 20 16 411 410 0 0 0 0 int8ne neqsel neqjoinsel ));
--- 122,133 ----
DATA(insert OID = 352 ( "=" PGNSP PGUID b t 28 28 16 352 0 0 0 0 0 xideq eqsel
eqjoinsel));
DATA(insert OID = 353 ( "=" PGNSP PGUID b f 28 23 16 0 0 0 0 0 0 xideqint4
eqseleqjoinsel ));
+ DATA(insert OID = 388 ( "!" PGNSP PGUID r f 20 0 1700 0 0 0 0 0 0 numeric_fac - - ));
+ DATA(insert OID = 389 ( "!!" PGNSP PGUID l f 0 20 1700 0 0 0 0 0 0 numeric_fac - - ));
DATA(insert OID = 385 ( "=" PGNSP PGUID b t 29 29 16 385 0 0 0 0 0 cideq eqsel
eqjoinsel));
DATA(insert OID = 386 ( "=" PGNSP PGUID b t 22 22 16 386 0 0 0 0 0 int2vectoreq
eqseleqjoinsel ));
DATA(insert OID = 387 ( "=" PGNSP PGUID b f 27 27 16 387 0 0 0 0 0 tideq eqsel
eqjoinsel));
#define TIDEqualOperator 387
DATA(insert OID = 410 ( "=" PGNSP PGUID b t 20 20 16 410 411 412 412 412 413 int8eq eqsel
eqjoinsel));
DATA(insert OID = 411 ( "<>" PGNSP PGUID b f 20 20 16 411 410 0 0 0 0 int8ne neqsel neqjoinsel ));
***************
*** 176,183 ****
DATA(insert OID = 512 ( "@" PGNSP PGUID b f 600 602 16 755 0 0 0 0 0 on_ppath - - ));
DATA(insert OID = 513 ( "@@" PGNSP PGUID l f 0 603 600 0 0 0 0 0 0 box_center - -
));
DATA(insert OID = 514 ( "*" PGNSP PGUID b f 23 23 23 514 0 0 0 0 0 int4mul - -
));
- DATA(insert OID = 515 ( "!" PGNSP PGUID r f 23 0 23 0 0 0 0 0 0 int4fac - -
));
- DATA(insert OID = 516 ( "!!" PGNSP PGUID l f 0 23 23 0 0 0 0 0 0 int4fac - -
));
DATA(insert OID = 517 ( "<->" PGNSP PGUID b f 600 600 701 517 0 0 0 0 0 point_distance - -
));
DATA(insert OID = 518 ( "<>" PGNSP PGUID b f 23 23 16 518 96 0 0 0 0 int4ne neqsel
neqjoinsel));
DATA(insert OID = 519 ( "<>" PGNSP PGUID b f 21 21 16 519 94 0 0 0 0 int2ne neqsel
neqjoinsel));
--- 176,181 ----
***************
*** 507,514 ****
DATA(insert OID = 1134 ( "<=" PGNSP PGUID b f 701 700 16 1125 1133 0 0 0 0 float84le scalarltsel
scalarltjoinsel));
DATA(insert OID = 1135 ( ">=" PGNSP PGUID b f 701 700 16 1124 1132 0 0 0 0 float84ge scalargtsel
scalargtjoinsel));
- DATA(insert OID = 1158 ( "!" PGNSP PGUID r f 21 0 23 0 0 0 0 0 0 int2fac - - ));
- DATA(insert OID = 1175 ( "!!" PGNSP PGUID l f 0 21 23 0 0 0 0 0 0 int2fac - - ));
/* LIKE hacks by Keith Parks. */
DATA(insert OID = 1207 ( "~~" PGNSP PGUID b f 19 25 16 0 1208 0 0 0 0 namelike likesel likejoinsel ));
--- 505,510 ----
Index: src/include/catalog/pg_proc.h
===================================================================
RCS file: /cvsroot/pgsql-server/src/include/catalog/pg_proc.h,v
retrieving revision 1.316
diff -c -c -r1.316 pg_proc.h
*** src/include/catalog/pg_proc.h 29 Nov 2003 22:40:58 -0000 1.316
--- src/include/catalog/pg_proc.h 1 Dec 2003 21:30:53 -0000
***************
*** 208,215 ****
/* OIDS 100 - 199 */
- DATA(insert OID = 100 ( int8fac PGNSP PGUID 12 f f t f i 1 20 "20" int8fac - _null_ ));
- DESCR("factorial");
DATA(insert OID = 101 ( eqsel PGNSP PGUID 12 f f t f s 4 701 "2281 26 2281 23" eqsel - _null_ ));
DESCR("restriction selectivity of = and related operators");
DATA(insert OID = 102 ( neqsel PGNSP PGUID 12 f f t f s 4 701 "2281 26 2281 23" neqsel - _null_ ));
--- 208,213 ----
***************
*** 231,237 ****
DESCR("I/O");
DATA(insert OID = 110 ( unknownout PGNSP PGUID 12 f f t f i 1 2275 "705" unknownout - _null_ ));
DESCR("I/O");
!
DATA(insert OID = 112 ( text PGNSP PGUID 12 f f t f i 1 25 "23" int4_text - _null_ ));
DESCR("convert int4 to text");
DATA(insert OID = 113 ( text PGNSP PGUID 12 f f t f i 1 25 "21" int2_text - _null_ ));
--- 229,235 ----
DESCR("I/O");
DATA(insert OID = 110 ( unknownout PGNSP PGUID 12 f f t f i 1 2275 "705" unknownout - _null_ ));
DESCR("I/O");
! DATA(insert OID = 111 ( numeric_fac PGNSP PGUID 12 f f t f i 1 1700 "20" numeric_fac - _null_ ));
DATA(insert OID = 112 ( text PGNSP PGUID 12 f f t f i 1 25 "23" int4_text - _null_ ));
DESCR("convert int4 to text");
DATA(insert OID = 113 ( text PGNSP PGUID 12 f f t f i 1 25 "21" int2_text - _null_ ));
***************
*** 294,301 ****
DESCR("join selectivity for area-comparison operators");
DATA(insert OID = 141 ( int4mul PGNSP PGUID 12 f f t f i 2 23 "23 23" int4mul - _null_ ));
DESCR("multiply");
- DATA(insert OID = 142 ( int4fac PGNSP PGUID 12 f f t f i 1 23 "23" int4fac - _null_ ));
- DESCR("factorial");
DATA(insert OID = 144 ( int4ne PGNSP PGUID 12 f f t f i 2 16 "23 23" int4ne - _null_ ));
DESCR("not equal");
DATA(insert OID = 145 ( int2ne PGNSP PGUID 12 f f t f i 2 16 "21 21" int2ne - _null_ ));
--- 292,297 ----
***************
*** 571,579 ****
DATA(insert OID = 275 ( isfinite PGNSP PGUID 12 f f t f i 1 16 "702" abstime_finite - _null_ ));
DESCR("finite abstime?");
- DATA(insert OID = 276 ( int2fac PGNSP PGUID 12 f f t f i 1 23 "21" int2fac - _null_ ));
- DESCR("factorial");
-
DATA(insert OID = 277 ( inter_sl PGNSP PGUID 12 f f t f i 2 16 "601 628" inter_sl - _null_ ));
DESCR("intersect?");
DATA(insert OID = 278 ( inter_lb PGNSP PGUID 12 f f t f i 2 16 "628 603" inter_lb - _null_ ));
--- 567,572 ----
***************
*** 1758,1768 ****
DESCR("finite interval?");
! DATA(insert OID = 1391 ( factorial PGNSP PGUID 12 f f t f i 1 23 "21" int2fac - _null_ ));
! DESCR("factorial");
! DATA(insert OID = 1392 ( factorial PGNSP PGUID 12 f f t f i 1 23 "23" int4fac - _null_ ));
! DESCR("factorial");
! DATA(insert OID = 1393 ( factorial PGNSP PGUID 12 f f t f i 1 20 "20" int8fac - _null_ ));
DESCR("factorial");
DATA(insert OID = 1394 ( abs PGNSP PGUID 12 f f t f i 1 700 "700" float4abs - _null_ ));
DESCR("absolute value");
--- 1751,1757 ----
DESCR("finite interval?");
! DATA(insert OID = 1376 ( factorial PGNSP PGUID 12 f f t f i 1 1700 "20" numeric_fac - _null_ ));
DESCR("factorial");
DATA(insert OID = 1394 ( abs PGNSP PGUID 12 f f t f i 1 700 "700" float4abs - _null_ ));
DESCR("absolute value");
Index: src/include/utils/builtins.h
===================================================================
RCS file: /cvsroot/pgsql-server/src/include/utils/builtins.h,v
retrieving revision 1.230
diff -c -c -r1.230 builtins.h
*** src/include/utils/builtins.h 29 Nov 2003 22:41:15 -0000 1.230
--- src/include/utils/builtins.h 1 Dec 2003 21:30:53 -0000
***************
*** 159,166 ****
extern Datum int2mod(PG_FUNCTION_ARGS);
extern Datum int24mod(PG_FUNCTION_ARGS);
extern Datum int42mod(PG_FUNCTION_ARGS);
- extern Datum int4fac(PG_FUNCTION_ARGS);
- extern Datum int2fac(PG_FUNCTION_ARGS);
extern Datum int2larger(PG_FUNCTION_ARGS);
extern Datum int2smaller(PG_FUNCTION_ARGS);
extern Datum int4larger(PG_FUNCTION_ARGS);
--- 159,164 ----
***************
*** 720,725 ****
--- 718,724 ----
extern Datum numeric_inc(PG_FUNCTION_ARGS);
extern Datum numeric_smaller(PG_FUNCTION_ARGS);
extern Datum numeric_larger(PG_FUNCTION_ARGS);
+ extern Datum numeric_fac(PG_FUNCTION_ARGS);
extern Datum numeric_sqrt(PG_FUNCTION_ARGS);
extern Datum numeric_exp(PG_FUNCTION_ARGS);
extern Datum numeric_ln(PG_FUNCTION_ARGS);
Index: src/include/utils/int8.h
===================================================================
RCS file: /cvsroot/pgsql-server/src/include/utils/int8.h,v
retrieving revision 1.39
diff -c -c -r1.39 int8.h
*** src/include/utils/int8.h 29 Nov 2003 22:41:15 -0000 1.39
--- src/include/utils/int8.h 1 Dec 2003 21:30:53 -0000
***************
*** 72,78 ****
extern Datum int8mul(PG_FUNCTION_ARGS);
extern Datum int8div(PG_FUNCTION_ARGS);
extern Datum int8abs(PG_FUNCTION_ARGS);
- extern Datum int8fac(PG_FUNCTION_ARGS);
extern Datum int8mod(PG_FUNCTION_ARGS);
extern Datum int8inc(PG_FUNCTION_ARGS);
extern Datum int8larger(PG_FUNCTION_ARGS);
--- 72,77 ----
Index: src/test/regress/expected/create_operator.out
===================================================================
RCS file: /cvsroot/pgsql-server/src/test/regress/expected/create_operator.out,v
retrieving revision 1.5
diff -c -c -r1.5 create_operator.out
*** src/test/regress/expected/create_operator.out 21 Nov 2003 22:32:49 -0000 1.5
--- src/test/regress/expected/create_operator.out 1 Dec 2003 21:30:54 -0000
***************
*** 15,33 ****
negator = >=%
);
CREATE OPERATOR @#@ (
! rightarg = int4, -- left unary
! procedure = int4fac
);
CREATE OPERATOR #@# (
! leftarg = int4, -- right unary
! procedure = int4fac
);
CREATE OPERATOR #%# (
! leftarg = int4, -- right unary
! procedure = int4fac
);
-- Test comments
COMMENT ON OPERATOR ###### (int4, NONE) IS 'bad right unary';
ERROR: operator does not exist: integer ######
- COMMENT ON OPERATOR #%# (int4, NONE) IS 'right unary';
- COMMENT ON OPERATOR #%# (int4, NONE) IS NULL;
--- 15,31 ----
negator = >=%
);
CREATE OPERATOR @#@ (
! rightarg = int8, -- left unary
! procedure = numeric_fac
);
CREATE OPERATOR #@# (
! leftarg = int8, -- right unary
! procedure = numeric_fac
);
CREATE OPERATOR #%# (
! leftarg = int8, -- right unary
! procedure = numeric_fac
);
-- Test comments
COMMENT ON OPERATOR ###### (int4, NONE) IS 'bad right unary';
ERROR: operator does not exist: integer ######
Index: src/test/regress/sql/create_operator.sql
===================================================================
RCS file: /cvsroot/pgsql-server/src/test/regress/sql/create_operator.sql,v
retrieving revision 1.5
diff -c -c -r1.5 create_operator.sql
*** src/test/regress/sql/create_operator.sql 21 Nov 2003 22:32:49 -0000 1.5
--- src/test/regress/sql/create_operator.sql 1 Dec 2003 21:30:54 -0000
***************
*** 18,40 ****
);
CREATE OPERATOR @#@ (
! rightarg = int4, -- left unary
! procedure = int4fac
);
CREATE OPERATOR #@# (
! leftarg = int4, -- right unary
! procedure = int4fac
);
CREATE OPERATOR #%# (
! leftarg = int4, -- right unary
! procedure = int4fac
);
-- Test comments
COMMENT ON OPERATOR ###### (int4, NONE) IS 'bad right unary';
- COMMENT ON OPERATOR #%# (int4, NONE) IS 'right unary';
- COMMENT ON OPERATOR #%# (int4, NONE) IS NULL;
--- 18,38 ----
);
CREATE OPERATOR @#@ (
! rightarg = int8, -- left unary
! procedure = numeric_fac
);
CREATE OPERATOR #@# (
! leftarg = int8, -- right unary
! procedure = numeric_fac
);
CREATE OPERATOR #%# (
! leftarg = int8, -- right unary
! procedure = numeric_fac
);
-- Test comments
COMMENT ON OPERATOR ###### (int4, NONE) IS 'bad right unary';
