From: Tom Lane Date: Fri, 22 Jan 2016 20:46:22 +0000 (-0500) Subject: Add trigonometric functions that work in degrees. X-Git-Tag: REL9_6_BETA1~828 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e1bd684a34c11139;p=postgresql Add trigonometric functions that work in degrees. The implementations go to some lengths to deliver exact results for values where an exact result can be expected, such as sind(30) = 0.5 exactly. Dean Rasheed, reviewed by Michael Paquier --- diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index 4d2b88fafd..9c143b2a63 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -1006,20 +1006,19 @@ Finally, shows the available trigonometric functions. All trigonometric functions take arguments and return values of type double - precision. Trigonometric functions arguments are expressed - in radians. Inverse functions return values are expressed in - radians. See unit transformation functions - radians() and - degrees() above. + precision. Each of the trigonometric functions comes in + two variants, one that measures angles in radians and one that + measures angles in degrees. Trigonometric Functions - + - Function + Function (radians) + Function (degrees) Description @@ -1031,6 +1030,11 @@ acosacos(x) + + + acosd + acosd(x) + inverse cosine @@ -1041,6 +1045,12 @@ asin(x) + + + asind + + asind(x) + inverse sine @@ -1051,6 +1061,12 @@ atan(x) + + + atand + + atand(x) + inverse tangent @@ -1062,6 +1078,13 @@ atan2(y, x) + + + atan2d + + atan2d(y, + x) + inverse tangent of y/x @@ -1073,6 +1096,12 @@ cos(x) + + + cosd + + cosd(x) + cosine @@ -1083,6 +1112,12 @@ cot(x) + + + cotd + + cotd(x) + cotangent @@ -1093,6 +1128,12 @@ sin(x) + + + sind + + sind(x) + sine @@ -1103,12 +1144,29 @@ tan(x) + + + tand + + tand(x) + tangent
+ + + Another way to work with angles measured in degrees is to use the unit + transformation functions radians() + and degrees() shown earlier. + However, using the degree-based trigonometric functions is preferred, + as that way avoids roundoff error for special cases such + as sind(30). + + + diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c index a3a989ed28..51e996ceb2 100644 --- a/src/backend/utils/adt/float.c +++ b/src/backend/utils/adt/float.c @@ -1601,7 +1601,7 @@ datan(PG_FUNCTION_ARGS) /* - * atan2 - returns the arctan2 of arg1 (radians) + * atan2 - returns the arctan of arg1/arg2 (radians) */ Datum datan2(PG_FUNCTION_ARGS) @@ -1744,6 +1744,441 @@ dtan(PG_FUNCTION_ARGS) } +/* + * asind_q1 - returns the inverse sine of x in degrees, for x in + * the range [0, 1]. The result is an angle in the + * first quadrant --- [0, 90] degrees. + * + * For the 3 special case inputs (0, 0.5 and 1), this + * function will return exact values (0, 30 and 90 + * degrees respectively). + */ +static double +asind_q1(double x) +{ + /* + * Stitch together inverse sine and cosine functions for the ranges [0, + * 0.5] and (0.5, 1]. Each expression below is guaranteed to return + * exactly 30 for x=0.5, so the result is a continuous monotonic function + * over the full range. + */ + if (x <= 0.5) + return (asin(x) / asin(0.5)) * 30.0; + else + return 90.0 - (acos(x) / acos(0.5)) * 60.0; +} + + +/* + * acosd_q1 - returns the inverse cosine of x in degrees, for x in + * the range [0, 1]. The result is an angle in the + * first quadrant --- [0, 90] degrees. + * + * For the 3 special case inputs (0, 0.5 and 1), this + * function will return exact values (0, 60 and 90 + * degrees respectively). + */ +static double +acosd_q1(double x) +{ + /* + * Stitch together inverse sine and cosine functions for the ranges [0, + * 0.5] and (0.5, 1]. Each expression below is guaranteed to return + * exactly 60 for x=0.5, so the result is a continuous monotonic function + * over the full range. + */ + if (x <= 0.5) + return 90.0 - (asin(x) / asin(0.5)) * 30.0; + else + return (acos(x) / acos(0.5)) * 60.0; +} + + +/* + * dacosd - returns the arccos of arg1 (degrees) + */ +Datum +dacosd(PG_FUNCTION_ARGS) +{ + float8 arg1 = PG_GETARG_FLOAT8(0); + float8 result; + + /* Per the POSIX spec, return NaN if the input is NaN */ + if (isnan(arg1)) + PG_RETURN_FLOAT8(get_float8_nan()); + + /* + * The principal branch of the inverse cosine function maps values in the + * range [-1, 1] to values in the range [0, 180], so we should reject any + * inputs outside that range and the result will always be finite. + */ + if (arg1 < -1.0 || arg1 > 1.0) + ereport(ERROR, + (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE), + errmsg("input is out of range"))); + + if (arg1 >= 0.0) + result = acosd_q1(arg1); + else + result = 90.0 + asind_q1(-arg1); + + CHECKFLOATVAL(result, false, true); + PG_RETURN_FLOAT8(result); +} + + +/* + * dasind - returns the arcsin of arg1 (degrees) + */ +Datum +dasind(PG_FUNCTION_ARGS) +{ + float8 arg1 = PG_GETARG_FLOAT8(0); + float8 result; + + /* Per the POSIX spec, return NaN if the input is NaN */ + if (isnan(arg1)) + PG_RETURN_FLOAT8(get_float8_nan()); + + /* + * The principal branch of the inverse sine function maps values in the + * range [-1, 1] to values in the range [-90, 90], so we should reject any + * inputs outside that range and the result will always be finite. + */ + if (arg1 < -1.0 || arg1 > 1.0) + ereport(ERROR, + (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE), + errmsg("input is out of range"))); + + if (arg1 >= 0.0) + result = asind_q1(arg1); + else + result = -asind_q1(-arg1); + + CHECKFLOATVAL(result, false, true); + PG_RETURN_FLOAT8(result); +} + + +/* + * datand - returns the arctan of arg1 (degrees) + */ +Datum +datand(PG_FUNCTION_ARGS) +{ + float8 arg1 = PG_GETARG_FLOAT8(0); + float8 result; + + /* Per the POSIX spec, return NaN if the input is NaN */ + if (isnan(arg1)) + PG_RETURN_FLOAT8(get_float8_nan()); + + /* + * The principal branch of the inverse tangent function maps all inputs to + * values in the range [-90, 90], so the result should always be finite, + * even if the input is infinite. Additionally, we take care to ensure + * than when arg1 is 1, the result is exactly 45. + */ + result = (atan(arg1) / atan(1.0)) * 45.0; + + CHECKFLOATVAL(result, false, true); + PG_RETURN_FLOAT8(result); +} + + +/* + * atan2d - returns the arctan of arg1/arg2 (degrees) + */ +Datum +datan2d(PG_FUNCTION_ARGS) +{ + float8 arg1 = PG_GETARG_FLOAT8(0); + float8 arg2 = PG_GETARG_FLOAT8(1); + float8 result; + + /* Per the POSIX spec, return NaN if either input is NaN */ + if (isnan(arg1) || isnan(arg2)) + PG_RETURN_FLOAT8(get_float8_nan()); + + /* + * atan2d maps all inputs to values in the range [-180, 180], so the + * result should always be finite, even if the inputs are infinite. + */ + result = (atan2(arg1, arg2) / atan(1.0)) * 45.0; + + CHECKFLOATVAL(result, false, true); + PG_RETURN_FLOAT8(result); +} + + +/* + * sind_0_to_30 - returns the sine of an angle that lies between 0 and + * 30 degrees. This will return exactly 0 when x is 0, + * and exactly 0.5 when x is 30 degrees. + */ +static double +sind_0_to_30(double x) +{ + return (sin(x * (M_PI / 180.0)) / sin(30.0 * (M_PI / 180.0))) / 2.0; +} + + +/* + * cosd_0_to_60 - returns the cosine of an angle that lies between 0 + * and 60 degrees. This will return exactly 1 when x + * is 0, and exactly 0.5 when x is 60 degrees. + */ +static double +cosd_0_to_60(double x) +{ + return 1.0 - ((1.0 - cos(x * (M_PI / 180.0))) / + (1.0 - cos(60.0 * (M_PI / 180.0)))) / 2.0; +} + + +/* + * sind_q1 - returns the sine of an angle in the first quadrant + * (0 to 90 degrees). + */ +static double +sind_q1(double x) +{ + /* + * Stitch together the sine and cosine functions for the ranges [0, 30] + * and (30, 90]. These guarantee to return exact answers at their + * endpoints, so the overall result is a continuous monotonic function + * that gives exact results when x = 0, 30 and 90 degrees. + */ + if (x <= 30.0) + return sind_0_to_30(x); + else + return cosd_0_to_60(90.0 - x); +} + + +/* + * cosd_q1 - returns the cosine of an angle in the first quadrant + * (0 to 90 degrees). + */ +static double +cosd_q1(double x) +{ + /* + * Stitch together the sine and cosine functions for the ranges [0, 60] + * and (60, 90]. These guarantee to return exact answers at their + * endpoints, so the overall result is a continuous monotonic function + * that gives exact results when x = 0, 60 and 90 degrees. + */ + if (x <= 60.0) + return cosd_0_to_60(x); + else + return sind_0_to_30(90.0 - x); +} + + +/* + * dcosd - returns the cosine of arg1 (degrees) + */ +Datum +dcosd(PG_FUNCTION_ARGS) +{ + float8 arg1 = PG_GETARG_FLOAT8(0); + int sign = 1; + float8 result; + + /* + * Per the POSIX spec, return NaN if the input is NaN and throw an error + * if the input is infinite. + */ + if (isnan(arg1)) + PG_RETURN_FLOAT8(get_float8_nan()); + + if (isinf(arg1)) + ereport(ERROR, + (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE), + errmsg("input is out of range"))); + + /* Reduce the range of the input to [0,90] degrees */ + arg1 = fmod(arg1, 360.0); + + if (arg1 < 0.0) + /* cosd(-x) = cosd(x) */ + arg1 = -arg1; + + if (arg1 > 180.0) + /* cosd(360-x) = cosd(x) */ + arg1 = 360.0 - arg1; + + if (arg1 > 90.0) + { + /* cosd(180-x) = -cosd(x) */ + arg1 = 180.0 - arg1; + sign = -sign; + } + + result = sign * cosd_q1(arg1); + + CHECKFLOATVAL(result, false, true); + PG_RETURN_FLOAT8(result); +} + + +/* + * dcotd - returns the cotangent of arg1 (degrees) + */ +Datum +dcotd(PG_FUNCTION_ARGS) +{ + float8 arg1 = PG_GETARG_FLOAT8(0); + int sign = 1; + float8 result; + + /* + * Per the POSIX spec, return NaN if the input is NaN and throw an error + * if the input is infinite. + */ + if (isnan(arg1)) + PG_RETURN_FLOAT8(get_float8_nan()); + + if (isinf(arg1)) + ereport(ERROR, + (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE), + errmsg("input is out of range"))); + + /* Reduce the range of the input to [0,90] degrees */ + arg1 = fmod(arg1, 360.0); + + if (arg1 < 0.0) + { + /* cotd(-x) = -cotd(x) */ + arg1 = -arg1; + sign = -sign; + } + + if (arg1 > 180.0) + { + /* cotd(360-x) = -cotd(x) */ + arg1 = 360.0 - arg1; + sign = -sign; + } + + if (arg1 > 90.0) + { + /* cotd(180-x) = -cotd(x) */ + arg1 = 180.0 - arg1; + sign = -sign; + } + + result = sign * cosd_q1(arg1) / sind_q1(arg1); + + CHECKFLOATVAL(result, true /* cotd(0) == Inf */ , true); + PG_RETURN_FLOAT8(result); +} + + +/* + * dsind - returns the sine of arg1 (degrees) + */ +Datum +dsind(PG_FUNCTION_ARGS) +{ + float8 arg1 = PG_GETARG_FLOAT8(0); + int sign = 1; + float8 result; + + /* + * Per the POSIX spec, return NaN if the input is NaN and throw an error + * if the input is infinite. + */ + if (isnan(arg1)) + PG_RETURN_FLOAT8(get_float8_nan()); + + if (isinf(arg1)) + ereport(ERROR, + (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE), + errmsg("input is out of range"))); + + /* Reduce the range of the input to [0,90] degrees */ + arg1 = fmod(arg1, 360.0); + + if (arg1 < 0.0) + { + /* sind(-x) = -sind(x) */ + arg1 = -arg1; + sign = -sign; + } + + if (arg1 > 180.0) + { + /* sind(360-x) = -sind(x) */ + arg1 = 360.0 - arg1; + sign = -sign; + } + + if (arg1 > 90.0) + /* sind(180-x) = sind(x) */ + arg1 = 180.0 - arg1; + + result = sign * sind_q1(arg1); + + CHECKFLOATVAL(result, false, true); + PG_RETURN_FLOAT8(result); +} + + +/* + * dtand - returns the tangent of arg1 (degrees) + */ +Datum +dtand(PG_FUNCTION_ARGS) +{ + float8 arg1 = PG_GETARG_FLOAT8(0); + int sign = 1; + float8 result; + + /* + * Per the POSIX spec, return NaN if the input is NaN and throw an error + * if the input is infinite. + */ + if (isnan(arg1)) + PG_RETURN_FLOAT8(get_float8_nan()); + + if (isinf(arg1)) + ereport(ERROR, + (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE), + errmsg("input is out of range"))); + + /* Reduce the range of the input to [0,90] degrees */ + arg1 = fmod(arg1, 360.0); + + if (arg1 < 0.0) + { + /* tand(-x) = -tand(x) */ + arg1 = -arg1; + sign = -sign; + } + + if (arg1 > 180.0) + { + /* tand(360-x) = -tand(x) */ + arg1 = 360.0 - arg1; + sign = -sign; + } + + if (arg1 > 90.0) + { + /* tand(180-x) = -tand(x) */ + arg1 = 180.0 - arg1; + sign = -sign; + } + + result = sign * sind_q1(arg1) / cosd_q1(arg1); + + CHECKFLOATVAL(result, true /* tand(90) == Inf */ , true); + PG_RETURN_FLOAT8(result); +} + + /* * degrees - returns degrees converted from radians */ diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h index 58709f56ac..894a619f94 100644 --- a/src/include/catalog/catversion.h +++ b/src/include/catalog/catversion.h @@ -53,6 +53,6 @@ */ /* yyyymmddN */ -#define CATALOG_VERSION_NO 201601201 +#define CATALOG_VERSION_NO 201601221 #endif diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h index 244aa4d016..79e92ffa78 100644 --- a/src/include/catalog/pg_proc.h +++ b/src/include/catalog/pg_proc.h @@ -1793,6 +1793,24 @@ DATA(insert OID = 1606 ( tan PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 DESCR("tangent"); DATA(insert OID = 1607 ( cot PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ dcot _null_ _null_ _null_ )); DESCR("cotangent"); + +DATA(insert OID = 2731 ( asind PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ dasind _null_ _null_ _null_ )); +DESCR("arcsine, degrees"); +DATA(insert OID = 2732 ( acosd PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ dacosd _null_ _null_ _null_ )); +DESCR("arccosine, degrees"); +DATA(insert OID = 2733 ( atand PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ datand _null_ _null_ _null_ )); +DESCR("arctangent, degrees"); +DATA(insert OID = 2734 ( atan2d PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 701 "701 701" _null_ _null_ _null_ _null_ _null_ datan2d _null_ _null_ _null_ )); +DESCR("arctangent, two arguments, degrees"); +DATA(insert OID = 2735 ( sind PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ dsind _null_ _null_ _null_ )); +DESCR("sine, degrees"); +DATA(insert OID = 2736 ( cosd PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ dcosd _null_ _null_ _null_ )); +DESCR("cosine, degrees"); +DATA(insert OID = 2737 ( tand PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ dtand _null_ _null_ _null_ )); +DESCR("tangent, degrees"); +DATA(insert OID = 2738 ( cotd PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ dcotd _null_ _null_ _null_ )); +DESCR("cotangent, degrees"); + DATA(insert OID = 1608 ( degrees PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ degrees _null_ _null_ _null_ )); DESCR("radians to degrees"); DATA(insert OID = 1609 ( radians PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 701 "701" _null_ _null_ _null_ _null_ _null_ radians _null_ _null_ _null_ )); diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h index 3c134a3aa9..c2e529fc6f 100644 --- a/src/include/utils/builtins.h +++ b/src/include/utils/builtins.h @@ -407,6 +407,14 @@ extern Datum dcos(PG_FUNCTION_ARGS); extern Datum dcot(PG_FUNCTION_ARGS); extern Datum dsin(PG_FUNCTION_ARGS); extern Datum dtan(PG_FUNCTION_ARGS); +extern Datum dacosd(PG_FUNCTION_ARGS); +extern Datum dasind(PG_FUNCTION_ARGS); +extern Datum datand(PG_FUNCTION_ARGS); +extern Datum datan2d(PG_FUNCTION_ARGS); +extern Datum dcosd(PG_FUNCTION_ARGS); +extern Datum dcotd(PG_FUNCTION_ARGS); +extern Datum dsind(PG_FUNCTION_ARGS); +extern Datum dtand(PG_FUNCTION_ARGS); extern Datum degrees(PG_FUNCTION_ARGS); extern Datum dpi(PG_FUNCTION_ARGS); extern Datum radians(PG_FUNCTION_ARGS); diff --git a/src/test/regress/expected/float8-exp-three-digits-win32.out b/src/test/regress/expected/float8-exp-three-digits-win32.out index 2dd648d6b9..6891ee0b4a 100644 --- a/src/test/regress/expected/float8-exp-three-digits-win32.out +++ b/src/test/regress/expected/float8-exp-three-digits-win32.out @@ -444,3 +444,80 @@ SELECT '' AS five, * FROM FLOAT8_TBL; | -1.2345678901234e-200 (5 rows) +-- test exact cases for trigonometric functions in degrees +SELECT x, + CASE WHEN sind(x) IN (-1,-0.5,0,0.5,1) THEN sind(x) END AS sind, + CASE WHEN cosd(x) IN (-1,-0.5,0,0.5,1) THEN cosd(x) END AS cosd, + CASE WHEN tand(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN tand(x) END AS tand, + CASE WHEN cotd(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN cotd(x) END AS cotd +FROM generate_series(0, 360, 15) AS t(x); + x | sind | cosd | tand | cotd +-----+------+------+-----------+----------- + 0 | 0 | 1 | 0 | Infinity + 15 | | | | + 30 | 0.5 | | | + 45 | | | 1 | 1 + 60 | | 0.5 | | + 75 | | | | + 90 | 1 | 0 | Infinity | 0 + 105 | | | | + 120 | | -0.5 | | + 135 | | | -1 | -1 + 150 | 0.5 | | | + 165 | | | | + 180 | 0 | -1 | -0 | -Infinity + 195 | | | | + 210 | -0.5 | | | + 225 | | | 1 | 1 + 240 | | -0.5 | | + 255 | | | | + 270 | -1 | 0 | -Infinity | -0 + 285 | | | | + 300 | | 0.5 | | + 315 | | | -1 | -1 + 330 | -0.5 | | | + 345 | | | | + 360 | 0 | 1 | 0 | Infinity +(25 rows) + +SELECT x, + CASE WHEN asind(x) IN (-90,-30,0,30,90) THEN asind(x) END AS asind, + CASE WHEN acosd(x) IN (0,60,90,120,180) THEN acosd(x) END AS acosd, + CASE WHEN atand(x) IN (-45,0,45) THEN atand(x) END AS atand +FROM (VALUES (-1), (-0.5), (0), (0.5), (1)) AS t(x); + x | asind | acosd | atand +------+-------+-------+------- + -1 | -90 | 180 | -45 + -0.5 | -30 | 120 | + 0 | 0 | 90 | 0 + 0.5 | 30 | 60 | + 1 | 90 | 0 | 45 +(5 rows) + +SELECT atand('-Infinity'::float8) = -90; + ?column? +---------- + t +(1 row) + +SELECT atand('Infinity'::float8) = 90; + ?column? +---------- + t +(1 row) + +SELECT x, y, + CASE WHEN atan2d(y, x) IN (-90,0,90,180) THEN atan2d(y, x) END AS atan2d +FROM (SELECT 10*cosd(a), 10*sind(a) + FROM generate_series(0, 360, 90) AS t(a)) AS t(x,y); + x | y | atan2d +-----+-----+-------- + 10 | 0 | 0 + 0 | 10 | 90 + -10 | 0 | 180 + 0 | -10 | -90 + 10 | 0 | 0 +(5 rows) + diff --git a/src/test/regress/expected/float8-small-is-zero.out b/src/test/regress/expected/float8-small-is-zero.out index 5da743374c..e158e7093a 100644 --- a/src/test/regress/expected/float8-small-is-zero.out +++ b/src/test/regress/expected/float8-small-is-zero.out @@ -442,3 +442,80 @@ SELECT '' AS five, * FROM FLOAT8_TBL; | -1.2345678901234e-200 (5 rows) +-- test exact cases for trigonometric functions in degrees +SELECT x, + CASE WHEN sind(x) IN (-1,-0.5,0,0.5,1) THEN sind(x) END AS sind, + CASE WHEN cosd(x) IN (-1,-0.5,0,0.5,1) THEN cosd(x) END AS cosd, + CASE WHEN tand(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN tand(x) END AS tand, + CASE WHEN cotd(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN cotd(x) END AS cotd +FROM generate_series(0, 360, 15) AS t(x); + x | sind | cosd | tand | cotd +-----+------+------+-----------+----------- + 0 | 0 | 1 | 0 | Infinity + 15 | | | | + 30 | 0.5 | | | + 45 | | | 1 | 1 + 60 | | 0.5 | | + 75 | | | | + 90 | 1 | 0 | Infinity | 0 + 105 | | | | + 120 | | -0.5 | | + 135 | | | -1 | -1 + 150 | 0.5 | | | + 165 | | | | + 180 | 0 | -1 | -0 | -Infinity + 195 | | | | + 210 | -0.5 | | | + 225 | | | 1 | 1 + 240 | | -0.5 | | + 255 | | | | + 270 | -1 | 0 | -Infinity | -0 + 285 | | | | + 300 | | 0.5 | | + 315 | | | -1 | -1 + 330 | -0.5 | | | + 345 | | | | + 360 | 0 | 1 | 0 | Infinity +(25 rows) + +SELECT x, + CASE WHEN asind(x) IN (-90,-30,0,30,90) THEN asind(x) END AS asind, + CASE WHEN acosd(x) IN (0,60,90,120,180) THEN acosd(x) END AS acosd, + CASE WHEN atand(x) IN (-45,0,45) THEN atand(x) END AS atand +FROM (VALUES (-1), (-0.5), (0), (0.5), (1)) AS t(x); + x | asind | acosd | atand +------+-------+-------+------- + -1 | -90 | 180 | -45 + -0.5 | -30 | 120 | + 0 | 0 | 90 | 0 + 0.5 | 30 | 60 | + 1 | 90 | 0 | 45 +(5 rows) + +SELECT atand('-Infinity'::float8) = -90; + ?column? +---------- + t +(1 row) + +SELECT atand('Infinity'::float8) = 90; + ?column? +---------- + t +(1 row) + +SELECT x, y, + CASE WHEN atan2d(y, x) IN (-90,0,90,180) THEN atan2d(y, x) END AS atan2d +FROM (SELECT 10*cosd(a), 10*sind(a) + FROM generate_series(0, 360, 90) AS t(a)) AS t(x,y); + x | y | atan2d +-----+-----+-------- + 10 | 0 | 0 + 0 | 10 | 90 + -10 | 0 | 180 + 0 | -10 | -90 + 10 | 0 | 0 +(5 rows) + diff --git a/src/test/regress/expected/float8-small-is-zero_1.out b/src/test/regress/expected/float8-small-is-zero_1.out index 530842e102..42e50a0464 100644 --- a/src/test/regress/expected/float8-small-is-zero_1.out +++ b/src/test/regress/expected/float8-small-is-zero_1.out @@ -442,3 +442,80 @@ SELECT '' AS five, * FROM FLOAT8_TBL; | -1.2345678901234e-200 (5 rows) +-- test exact cases for trigonometric functions in degrees +SELECT x, + CASE WHEN sind(x) IN (-1,-0.5,0,0.5,1) THEN sind(x) END AS sind, + CASE WHEN cosd(x) IN (-1,-0.5,0,0.5,1) THEN cosd(x) END AS cosd, + CASE WHEN tand(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN tand(x) END AS tand, + CASE WHEN cotd(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN cotd(x) END AS cotd +FROM generate_series(0, 360, 15) AS t(x); + x | sind | cosd | tand | cotd +-----+------+------+-----------+----------- + 0 | 0 | 1 | 0 | Infinity + 15 | | | | + 30 | 0.5 | | | + 45 | | | 1 | 1 + 60 | | 0.5 | | + 75 | | | | + 90 | 1 | 0 | Infinity | 0 + 105 | | | | + 120 | | -0.5 | | + 135 | | | -1 | -1 + 150 | 0.5 | | | + 165 | | | | + 180 | 0 | -1 | -0 | -Infinity + 195 | | | | + 210 | -0.5 | | | + 225 | | | 1 | 1 + 240 | | -0.5 | | + 255 | | | | + 270 | -1 | 0 | -Infinity | -0 + 285 | | | | + 300 | | 0.5 | | + 315 | | | -1 | -1 + 330 | -0.5 | | | + 345 | | | | + 360 | 0 | 1 | 0 | Infinity +(25 rows) + +SELECT x, + CASE WHEN asind(x) IN (-90,-30,0,30,90) THEN asind(x) END AS asind, + CASE WHEN acosd(x) IN (0,60,90,120,180) THEN acosd(x) END AS acosd, + CASE WHEN atand(x) IN (-45,0,45) THEN atand(x) END AS atand +FROM (VALUES (-1), (-0.5), (0), (0.5), (1)) AS t(x); + x | asind | acosd | atand +------+-------+-------+------- + -1 | -90 | 180 | -45 + -0.5 | -30 | 120 | + 0 | 0 | 90 | 0 + 0.5 | 30 | 60 | + 1 | 90 | 0 | 45 +(5 rows) + +SELECT atand('-Infinity'::float8) = -90; + ?column? +---------- + t +(1 row) + +SELECT atand('Infinity'::float8) = 90; + ?column? +---------- + t +(1 row) + +SELECT x, y, + CASE WHEN atan2d(y, x) IN (-90,0,90,180) THEN atan2d(y, x) END AS atan2d +FROM (SELECT 10*cosd(a), 10*sind(a) + FROM generate_series(0, 360, 90) AS t(a)) AS t(x,y); + x | y | atan2d +-----+-----+-------- + 10 | 0 | 0 + 0 | 10 | 90 + -10 | 0 | 180 + 0 | -10 | -90 + 10 | 0 | 0 +(5 rows) + diff --git a/src/test/regress/expected/float8.out b/src/test/regress/expected/float8.out index 6221538af5..b77b34f2b3 100644 --- a/src/test/regress/expected/float8.out +++ b/src/test/regress/expected/float8.out @@ -444,3 +444,80 @@ SELECT '' AS five, * FROM FLOAT8_TBL; | -1.2345678901234e-200 (5 rows) +-- test exact cases for trigonometric functions in degrees +SELECT x, + CASE WHEN sind(x) IN (-1,-0.5,0,0.5,1) THEN sind(x) END AS sind, + CASE WHEN cosd(x) IN (-1,-0.5,0,0.5,1) THEN cosd(x) END AS cosd, + CASE WHEN tand(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN tand(x) END AS tand, + CASE WHEN cotd(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN cotd(x) END AS cotd +FROM generate_series(0, 360, 15) AS t(x); + x | sind | cosd | tand | cotd +-----+------+------+-----------+----------- + 0 | 0 | 1 | 0 | Infinity + 15 | | | | + 30 | 0.5 | | | + 45 | | | 1 | 1 + 60 | | 0.5 | | + 75 | | | | + 90 | 1 | 0 | Infinity | 0 + 105 | | | | + 120 | | -0.5 | | + 135 | | | -1 | -1 + 150 | 0.5 | | | + 165 | | | | + 180 | 0 | -1 | -0 | -Infinity + 195 | | | | + 210 | -0.5 | | | + 225 | | | 1 | 1 + 240 | | -0.5 | | + 255 | | | | + 270 | -1 | 0 | -Infinity | -0 + 285 | | | | + 300 | | 0.5 | | + 315 | | | -1 | -1 + 330 | -0.5 | | | + 345 | | | | + 360 | 0 | 1 | 0 | Infinity +(25 rows) + +SELECT x, + CASE WHEN asind(x) IN (-90,-30,0,30,90) THEN asind(x) END AS asind, + CASE WHEN acosd(x) IN (0,60,90,120,180) THEN acosd(x) END AS acosd, + CASE WHEN atand(x) IN (-45,0,45) THEN atand(x) END AS atand +FROM (VALUES (-1), (-0.5), (0), (0.5), (1)) AS t(x); + x | asind | acosd | atand +------+-------+-------+------- + -1 | -90 | 180 | -45 + -0.5 | -30 | 120 | + 0 | 0 | 90 | 0 + 0.5 | 30 | 60 | + 1 | 90 | 0 | 45 +(5 rows) + +SELECT atand('-Infinity'::float8) = -90; + ?column? +---------- + t +(1 row) + +SELECT atand('Infinity'::float8) = 90; + ?column? +---------- + t +(1 row) + +SELECT x, y, + CASE WHEN atan2d(y, x) IN (-90,0,90,180) THEN atan2d(y, x) END AS atan2d +FROM (SELECT 10*cosd(a), 10*sind(a) + FROM generate_series(0, 360, 90) AS t(a)) AS t(x,y); + x | y | atan2d +-----+-----+-------- + 10 | 0 | 0 + 0 | 10 | 90 + -10 | 0 | 180 + 0 | -10 | -90 + 10 | 0 | 0 +(5 rows) + diff --git a/src/test/regress/sql/float8.sql b/src/test/regress/sql/float8.sql index 92a574ab7b..45a484b8b9 100644 --- a/src/test/regress/sql/float8.sql +++ b/src/test/regress/sql/float8.sql @@ -167,3 +167,27 @@ INSERT INTO FLOAT8_TBL(f1) VALUES ('-1.2345678901234e+200'); INSERT INTO FLOAT8_TBL(f1) VALUES ('-1.2345678901234e-200'); SELECT '' AS five, * FROM FLOAT8_TBL; + +-- test exact cases for trigonometric functions in degrees +SELECT x, + CASE WHEN sind(x) IN (-1,-0.5,0,0.5,1) THEN sind(x) END AS sind, + CASE WHEN cosd(x) IN (-1,-0.5,0,0.5,1) THEN cosd(x) END AS cosd, + CASE WHEN tand(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN tand(x) END AS tand, + CASE WHEN cotd(x) IN ('-Infinity'::float8,-1,0, + 1,'Infinity'::float8) THEN cotd(x) END AS cotd +FROM generate_series(0, 360, 15) AS t(x); + +SELECT x, + CASE WHEN asind(x) IN (-90,-30,0,30,90) THEN asind(x) END AS asind, + CASE WHEN acosd(x) IN (0,60,90,120,180) THEN acosd(x) END AS acosd, + CASE WHEN atand(x) IN (-45,0,45) THEN atand(x) END AS atand +FROM (VALUES (-1), (-0.5), (0), (0.5), (1)) AS t(x); + +SELECT atand('-Infinity'::float8) = -90; +SELECT atand('Infinity'::float8) = 90; + +SELECT x, y, + CASE WHEN atan2d(y, x) IN (-90,0,90,180) THEN atan2d(y, x) END AS atan2d +FROM (SELECT 10*cosd(a), 10*sind(a) + FROM generate_series(0, 360, 90) AS t(a)) AS t(x,y);