round(unit) rounds unit to nearest integer

Part of #11.

Author: df7cb

Makefile

@@ -5,7 +5,8 @@ DATA = unit_prefixes.data unit_units.data \
 	   unit--1.sql unit--1--2.sql \
 	   unit--2.sql
 DATA_built = unit--2--3.sql unit--3.sql \
-			 unit--3--4.sql unit--4.sql
+			 unit--3--4.sql unit--4.sql \
+			 unit--4--5.sql unit--5.sql
 REGRESS = extension tables unit unicode prefix units temperature functions derived compare aggregate iec custom
 EXTRA_CLEAN = unitparse.yy.* powers powers.o unit-*.dump # unitparse.tab.*
 

README.md

@@ -266,6 +266,7 @@ function cbrt(unit)
 function dimension(unit)
 function max(unit)
 function min(unit)
+function round(unit)
 function sqrt(unit)
 function stddev_pop(unit)
 function stddev_samp(unit)
@@ -318,6 +319,10 @@ Details:
 
   Returns the numeric part of a unit value.
 
+* **function round(unit): unit**
+
+  Rounds a unit value to the nearest integer (in base units).
+
 References
 ----------
 

debian/changelog

@@ -1,10 +1,11 @@
-postgresql-unit (4.0-3) UNRELEASED; urgency=medium
+postgresql-unit (5.0-1) UNRELEASED; urgency=medium
 
+  * Add rounding functions.
   * Import definitions.units from GNU units 2.16 with 70 new units.
     (The file header erroneously says 2.19.)
   * debian/watch: Ignore debian/ tags.
 
- -- Christoph Berg <[email protected]>  Tue, 28 Nov 2017 20:23:01 +0100
+ -- Christoph Berg <[email protected]>  Tue, 02 Jan 2018 18:53:55 +0100
 
 postgresql-unit (4.0-2) unstable; urgency=medium
 

expected/functions.out

@@ -1,4 +1,4 @@
--- text extractors
+-- text functions
 SELECT value('2'::unit);
  value 
 -------
@@ -23,6 +23,18 @@ SELECT dimension(kilogram(2));
  1 kg
 (1 row)
 
+SELECT round(ampere(1.5));
+ round 
+-------
+ 2 A
+(1 row)
+
+SELECT round(candela(-0.5));
+ round 
+-------
+ -1 cd
+(1 row)
+
 -- test unit addition/subtraction
 SELECT '1'::unit + '2' AS sum;
  sum 

sql/functions.sql

@@ -1,8 +1,10 @@
--- text extractors
+-- test functions
 SELECT value('2'::unit);
 SELECT value(meter(2));
 SELECT dimension('2'::unit);
 SELECT dimension(kilogram(2));
+SELECT round(ampere(1.5));
+SELECT round(candela(-0.5));
 
 -- test unit addition/subtraction
 SELECT '1'::unit + '2' AS sum;

unit--4--5.sql.in

@@ -0,0 +1,4 @@
+CREATE FUNCTION round(unit)
+	RETURNS unit
+	AS '$libdir/unit', 'unit_round'
+	LANGUAGE C IMMUTABLE STRICT;