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unit--6.sql.in
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unit--6.sql.in
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/*
Copyright (C) 2016-2018 Christoph Berg
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
*/
-- type definition
CREATE TYPE unit;
CREATE FUNCTION unit_in(cstring)
RETURNS unit
SET search_path = @extschema@
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION unit_out(unit)
RETURNS cstring
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE TYPE unit (
internallength = 16,
input = unit_in,
output = unit_out,
alignment = double
);
-- prefix/unit definition tables
CREATE TABLE unit_prefixes (
prefix varchar(32) PRIMARY KEY,
factor double precision NOT NULL,
definition text, -- original definition, informational
dump boolean DEFAULT true
);
SELECT pg_catalog.pg_extension_config_dump('unit_prefixes', 'WHERE dump');
CREATE TABLE unit_units (
name varchar(32) PRIMARY KEY,
unit unit NOT NULL,
shift double precision, -- NULL means 0.0 here
definition text, -- original definition, informational
dump boolean DEFAULT true
);
SELECT pg_catalog.pg_extension_config_dump('unit_units', 'WHERE dump');
GRANT SELECT ON unit_prefixes, unit_units TO PUBLIC;
CREATE FUNCTION unit_load()
RETURNS VOID
LANGUAGE plpgsql
AS $$BEGIN
DELETE FROM unit_prefixes WHERE dump IS NOT TRUE;
CREATE TEMP TABLE tmp_prefixes (LIKE unit_prefixes) ON COMMIT DROP;
COPY tmp_prefixes (prefix, factor, definition, dump) FROM '@MODULEDIR@/unit_prefixes.data';
INSERT INTO unit_prefixes
SELECT * FROM tmp_prefixes t WHERE NOT EXISTS
(SELECT prefix FROM unit_prefixes u WHERE u.prefix = t.prefix);
DROP TABLE tmp_prefixes;
DELETE FROM unit_units WHERE dump IS NOT TRUE;
CREATE TEMP TABLE tmp_units (LIKE unit_units) ON COMMIT DROP;
COPY tmp_units (name, unit, shift, definition, dump) FROM '@MODULEDIR@/unit_units.data';
INSERT INTO unit_units
SELECT * FROM tmp_units t WHERE NOT EXISTS
(SELECT name FROM unit_units u WHERE u.name = t.name);
DROP TABLE tmp_units;
END;$$;
COMMENT ON FUNCTION unit_load() IS 'Loads/upgrades the unit_units and unit_prefixes contents from the data files on disk';
SELECT unit_load();
-- constructors
CREATE FUNCTION unit(double precision DEFAULT 1.0)
RETURNS unit
AS '$libdir/unit', 'dbl2unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION meter(double precision DEFAULT 1.0)
RETURNS unit
AS '$libdir/unit', 'unit_meter'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION kilogram(double precision DEFAULT 1.0)
RETURNS unit
AS '$libdir/unit', 'unit_kilogram'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION second(double precision DEFAULT 1.0)
RETURNS unit
AS '$libdir/unit', 'unit_second'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION ampere(double precision DEFAULT 1.0)
RETURNS unit
AS '$libdir/unit', 'unit_ampere'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION kelvin(double precision DEFAULT 1.0)
RETURNS unit
AS '$libdir/unit', 'unit_kelvin'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION mole(double precision DEFAULT 1.0)
RETURNS unit
AS '$libdir/unit', 'unit_mole'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION candela(double precision DEFAULT 1.0)
RETURNS unit
AS '$libdir/unit', 'unit_candela'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION byte(double precision DEFAULT 1.0)
RETURNS unit
AS '$libdir/unit', 'unit_byte'
LANGUAGE C IMMUTABLE STRICT;
-- functions without operators
CREATE FUNCTION value(unit)
RETURNS double precision
AS '$libdir/unit', 'unit_value'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION dimension(unit)
RETURNS unit
AS '$libdir/unit', 'unit_dimension'
LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION round(unit)
RETURNS unit
AS '$libdir/unit', 'unit_round'
LANGUAGE C IMMUTABLE STRICT;
-- operators
CREATE FUNCTION unit_add(unit, unit)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR + (
leftarg = unit,
rightarg = unit,
procedure = unit_add,
commutator = +
);
CREATE FUNCTION unit_sub(unit, unit)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR - (
leftarg = unit,
rightarg = unit,
procedure = unit_sub
);
CREATE FUNCTION unit_neg(unit)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR - (
rightarg = unit,
procedure = unit_neg
);
CREATE FUNCTION unit_mul(unit, unit)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR * (
leftarg = unit,
rightarg = unit,
procedure = unit_mul,
commutator = *
);
CREATE FUNCTION dbl_unit_mul(double precision, unit)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR * (
leftarg = double precision,
rightarg = unit,
procedure = dbl_unit_mul,
commutator = *
);
CREATE FUNCTION unit_dbl_mul(unit, double precision)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR * (
leftarg = unit,
rightarg = double precision,
procedure = unit_dbl_mul,
commutator = *
);
CREATE FUNCTION unit_div(unit, unit)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR / (
leftarg = unit,
rightarg = unit,
procedure = unit_div
);
CREATE FUNCTION dbl_unit_div(double precision, unit)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR / (
leftarg = double precision,
rightarg = unit,
procedure = dbl_unit_div
);
CREATE FUNCTION unit_dbl_div(unit, double precision)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR / (
leftarg = unit,
rightarg = double precision,
procedure = unit_dbl_div
);
CREATE FUNCTION unit_pow(unit, int)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR ^ (
leftarg = unit,
rightarg = int,
procedure = unit_pow
);
CREATE FUNCTION sqrt(unit)
RETURNS unit
AS '$libdir/unit', 'unit_sqrt'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR |/ (
rightarg = unit,
procedure = sqrt
);
CREATE FUNCTION cbrt(unit)
RETURNS unit
AS '$libdir/unit', 'unit_cbrt'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR ||/ (
rightarg = unit,
procedure = cbrt
);
CREATE FUNCTION unit_at(unit, text)
RETURNS cstring
SET search_path = @extschema@
AS '$libdir/unit', 'unit_at_text'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR @ (
leftarg = unit,
rightarg = text,
procedure = unit_at
);
CREATE FUNCTION unit_at_double(unit, text)
RETURNS double precision
SET search_path = @extschema@
AS '$libdir/unit', 'unit_at_double'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR @@ (
leftarg = unit,
rightarg = text,
procedure = unit_at_double
);
-- derived units
CREATE FUNCTION radian (double precision DEFAULT 1.0) -- m·m^-1
RETURNS unit
AS $$SELECT meter($1) / meter()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION steradian (double precision DEFAULT 1.0) -- m^2·m^-2
RETURNS unit
AS $$SELECT meter($1) * meter() / meter()^2$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION hertz (double precision DEFAULT 1.0) -- s^-1
RETURNS unit
AS $$SELECT $1 / second()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION newton (double precision DEFAULT 1.0) -- kg·m·s^-2
RETURNS unit
AS $$SELECT kilogram($1) * meter() / second()^2$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION pascal (double precision DEFAULT 1.0) -- N/m^2
RETURNS unit
AS $$SELECT newton($1) / meter()^2 $$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION joule (double precision DEFAULT 1.0) -- N·m
RETURNS unit
AS $$SELECT newton($1) * meter()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION watt (double precision DEFAULT 1.0) -- J/s
RETURNS unit
AS $$SELECT joule($1) / second()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION coulomb (double precision DEFAULT 1.0) -- A·s
RETURNS unit
AS $$SELECT ampere($1) * second()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION volt (double precision DEFAULT 1.0) -- W/A
RETURNS unit
AS $$SELECT watt($1) / ampere() $$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION farad (double precision DEFAULT 1.0) -- C/V
RETURNS unit
AS $$SELECT coulomb($1) / volt() $$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION ohm (double precision DEFAULT 1.0) -- V/A
RETURNS unit
AS $$SELECT volt($1) / ampere() $$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION siemens (double precision DEFAULT 1.0) -- A/V
RETURNS unit
AS $$SELECT ampere($1) / volt()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION weber (double precision DEFAULT 1.0) -- V·s
RETURNS unit
AS $$SELECT volt($1) * second()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION tesla (double precision DEFAULT 1.0) -- Wb/m^2
RETURNS unit
AS $$SELECT weber($1) / meter()^2$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION henry (double precision DEFAULT 1.0) -- Wb/A
RETURNS unit
AS $$SELECT weber($1) / ampere()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION celsius (double precision DEFAULT 0.0) -- K relative to 273.15, default to 0°C
RETURNS unit
AS $$SELECT kelvin($1 + 273.15)$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION lumen (double precision DEFAULT 1.0) -- cd·sr
RETURNS unit
AS $$SELECT candela($1) * steradian()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION lux (double precision DEFAULT 1.0) -- lm/m^2
RETURNS unit
AS $$SELECT lumen($1) / meter()^2$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION becquerel (double precision DEFAULT 1.0) -- s^-1
RETURNS unit
AS $$SELECT $1 / second()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION gray (double precision DEFAULT 1.0) -- J/kg
RETURNS unit
AS $$SELECT joule($1) / kilogram()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION sievert (double precision DEFAULT 1.0) -- J/kg
RETURNS unit
AS $$SELECT joule($1)/ kilogram()$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION katal (double precision DEFAULT 1.0) -- mol·s^-1
RETURNS unit
AS $$SELECT mole($1) / second()$$
LANGUAGE SQL IMMUTABLE STRICT;
-- Non-SI units accepted for use with the SI
--minute, hour, day, degree of arc, minute of arc, second of arc, hectare, litre, tonne, astronomical unit and [deci]bel
CREATE FUNCTION minute (double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT second($1 * 60)$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION hour (double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT second($1 * 3600)$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION day (double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT second($1 * 86400)$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION degree_arc(double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT $1 * '1'::unit * pi() / 180$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION minute_arc(double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT $1 * '1'::unit * pi() / 180 / 60$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION second_arc(double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT $1 * '1'::unit * pi() / 180 / 3600$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION hectare (double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT $1 * meter(100)^2$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION liter (double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT $1 * meter(0.1)^3$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION tonne (double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT kilogram($1 * 1000)$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION au (double precision DEFAULT 1.0)
RETURNS unit
AS $$SELECT meter($1 * 149597870700)$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION decibel (double precision DEFAULT 0.0)
RETURNS double precision
AS $$SELECT 10.0^($1 / 10.0)$$
LANGUAGE SQL IMMUTABLE STRICT;
-- comparisons
CREATE FUNCTION unit_lt(unit, unit) RETURNS bool
AS '$libdir/unit' LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION unit_le(unit, unit) RETURNS bool
AS '$libdir/unit' LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION unit_eq(unit, unit) RETURNS bool
AS '$libdir/unit' LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION unit_ne(unit, unit) RETURNS bool
AS '$libdir/unit' LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION unit_ge(unit, unit) RETURNS bool
AS '$libdir/unit' LANGUAGE C IMMUTABLE STRICT;
CREATE FUNCTION unit_gt(unit, unit) RETURNS bool
AS '$libdir/unit' LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR < (
leftarg = unit, rightarg = unit, procedure = unit_lt,
commutator = > , negator = >= ,
restrict = scalarltsel, join = scalarltjoinsel
);
CREATE OPERATOR <= (
leftarg = unit, rightarg = unit, procedure = unit_le,
commutator = >= , negator = > ,
restrict = scalarltsel, join = scalarltjoinsel
);
CREATE OPERATOR = (
leftarg = unit, rightarg = unit, procedure = unit_eq,
commutator = = , negator = <> ,
restrict = eqsel, join = eqjoinsel
);
CREATE OPERATOR <> (
leftarg = unit, rightarg = unit, procedure = unit_ne,
commutator = <> , negator = = ,
restrict = neqsel, join = neqjoinsel
);
CREATE OPERATOR >= (
leftarg = unit, rightarg = unit, procedure = unit_ge,
commutator = <= , negator = < ,
restrict = scalargtsel, join = scalargtjoinsel
);
CREATE OPERATOR > (
leftarg = unit, rightarg = unit, procedure = unit_gt,
commutator = < , negator = <= ,
restrict = scalargtsel, join = scalargtjoinsel
);
CREATE FUNCTION unit_cmp(unit, unit)
RETURNS int4
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE OPERATOR CLASS unit_ops
DEFAULT FOR TYPE unit USING btree AS
OPERATOR 1 < ,
OPERATOR 2 <= ,
OPERATOR 3 = ,
OPERATOR 4 >= ,
OPERATOR 5 > ,
FUNCTION 1 unit_cmp(unit, unit);
-- aggregates
CREATE AGGREGATE sum(unit)
(
sfunc = unit_add,
stype = unit
);
CREATE FUNCTION unit_least(unit, unit)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE AGGREGATE min(unit)
(
sfunc = unit_least,
stype = unit
);
CREATE FUNCTION unit_greatest(unit, unit)
RETURNS unit
AS '$libdir/unit'
LANGUAGE C IMMUTABLE STRICT;
CREATE AGGREGATE max(unit)
(
sfunc = unit_greatest,
stype = unit
);
CREATE TYPE unit_accum_t AS (
s unit,
squares double precision,
n bigint
);
CREATE FUNCTION unit_accum(a unit_accum_t, u unit)
RETURNS unit_accum_t
AS $$SELECT (CASE WHEN a.s = '0'::unit THEN u ELSE a.s + u END, a.squares + value(u)^2, a.n + 1)::unit_accum_t$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE FUNCTION unit_avg(a unit_accum_t)
RETURNS unit
AS $$SELECT CASE WHEN a.n > 0 THEN a.s / a.n ELSE NULL END$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE AGGREGATE avg(unit)
(
sfunc = unit_accum,
stype = unit_accum_t,
finalfunc = unit_avg,
initcond = '(0,0,0)'
);
CREATE FUNCTION unit_var_pop(a unit_accum_t)
RETURNS double precision
AS $$SELECT CASE WHEN a.n > 0 THEN (a.squares - value(a.s)^2 / a.n) / a.n ELSE NULL END$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE AGGREGATE var_pop(unit)
(
sfunc = unit_accum,
stype = unit_accum_t,
finalfunc = unit_var_pop,
initcond = '(0,0,0)'
);
CREATE FUNCTION unit_var_samp(a unit_accum_t)
RETURNS double precision
AS $$SELECT CASE WHEN a.n > 1 THEN (a.squares - value(a.s)^2 / a.n) / (a.n - 1) WHEN a.n = 1 THEN 0 ELSE NULL END$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE AGGREGATE var_samp(unit)
(
sfunc = unit_accum,
stype = unit_accum_t,
finalfunc = unit_var_samp,
initcond = '(0,0,0)'
);
CREATE AGGREGATE variance(unit)
(
sfunc = unit_accum,
stype = unit_accum_t,
finalfunc = unit_var_samp,
initcond = '(0,0,0)'
);
CREATE FUNCTION unit_stddev_pop(a unit_accum_t)
RETURNS unit
AS $$SELECT CASE WHEN a.n > 0 THEN sqrt((a.squares - value(a.s)^2 / a.n) / a.n) * dimension(a.s) ELSE NULL END$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE AGGREGATE stddev_pop(unit)
(
sfunc = unit_accum,
stype = unit_accum_t,
finalfunc = unit_stddev_pop,
initcond = '(0,0,0)'
);
CREATE FUNCTION unit_stddev_samp(a unit_accum_t)
RETURNS unit
AS $$SELECT CASE WHEN a.n > 1 THEN sqrt((a.squares - value(a.s)^2 / a.n) / (a.n - 1)) * dimension(a.s) WHEN a.n = 1 THEN 0 * dimension(a.s) ELSE NULL END$$
LANGUAGE SQL IMMUTABLE STRICT;
CREATE AGGREGATE stddev_samp(unit)
(
sfunc = unit_accum,
stype = unit_accum_t,
finalfunc = unit_stddev_samp,
initcond = '(0,0,0)'
);
CREATE AGGREGATE stddev(unit)
(
sfunc = unit_accum,
stype = unit_accum_t,
finalfunc = unit_stddev_samp,
initcond = '(0,0,0)'
);
-- internal functions
CREATE FUNCTION unit_is_hashed(cstring)
RETURNS bool
AS '$libdir/unit'
LANGUAGE C VOLATILE STRICT;
CREATE FUNCTION unit_reset()
RETURNS void
AS '$libdir/unit'
LANGUAGE C VOLATILE STRICT;