Implement functions in parser: sqrt exp ln log2 asin tan

Author: df7cb

unit.c

@@ -907,21 +907,16 @@ unit_pow(PG_FUNCTION_ARGS)
 	PG_RETURN_POINTER(result);
 }
 
-PG_FUNCTION_INFO_V1(unit_sqrt);
-
-Datum
-unit_sqrt(PG_FUNCTION_ARGS)
+void
+unit_sqrt_internal(Unit *a, Unit *result)
 {
-	Unit	*a = (Unit *) PG_GETARG_POINTER(0);
-	Unit	*result;
 	int		 i;
 
 	/* compute root of value */
 	if (a->value < 0)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_ARGUMENT_FOR_POWER_FUNCTION),
 				 errmsg("cannot take square root of a negative-valued unit")));
-	result = (Unit *) palloc(sizeof(Unit));
 	result->value = sqrt(a->value);
 
 	/* compute root of base units */
@@ -934,7 +929,17 @@ unit_sqrt(PG_FUNCTION_ARGS)
 						 base_units[i])));
 		result->units[i] = a->units[i] >> 1;
 	}
+}
+
+PG_FUNCTION_INFO_V1(unit_sqrt);
+
+Datum
+unit_sqrt(PG_FUNCTION_ARGS)
+{
+	Unit	*a = (Unit *) PG_GETARG_POINTER(0);
+	Unit	*result = (Unit *) palloc(sizeof(Unit));
 
+	unit_sqrt_internal(a, result);
 	PG_RETURN_POINTER(result);
 }
 
@@ -965,6 +970,105 @@ unit_cbrt(PG_FUNCTION_ARGS)
 	PG_RETURN_POINTER(result);
 }
 
+void
+unit_exp_internal(Unit *a, Unit *result)
+{
+	int		 i;
+
+	/* compute exp of value */
+	result->value = exp(a->value);
+
+	/* check dimension */
+	for (i = 0; i < N_UNITS; i++)
+	{
+		if (a->units[i] != 0)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_ARGUMENT_FOR_POWER_FUNCTION),
+					 errmsg("cannot take base-e exponent of value that is not dimension-less")));
+		result->units[i] = 0;
+	}
+}
+
+void
+unit_ln_internal(Unit *a, Unit *result)
+{
+	int		 i;
+
+	/* compute ln of value */
+	result->value = log(a->value);
+
+	/* check dimension */
+	for (i = 0; i < N_UNITS; i++)
+	{
+		if (a->units[i] != 0)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_ARGUMENT_FOR_POWER_FUNCTION),
+					 errmsg("cannot take ln of value that is not dimension-less")));
+		result->units[i] = 0;
+	}
+}
+
+void
+unit_log2_internal(Unit *a, Unit *result)
+{
+	int		 i;
+
+	/* compute log2 of value */
+	result->value = log2(a->value);
+
+	/* check dimension */
+	for (i = 0; i < N_UNITS; i++)
+	{
+		if (a->units[i] != 0)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_ARGUMENT_FOR_POWER_FUNCTION),
+					 errmsg("cannot take log2 of value that is not dimension-less")));
+		result->units[i] = 0;
+	}
+}
+
+void
+unit_asin_internal(Unit *a, Unit *result)
+{
+	int		 i;
+
+	/* compute asin of value */
+	if (a->value < -1 || a->value > 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_ARGUMENT_FOR_POWER_FUNCTION),
+				 errmsg("cannot asin of values outside the range -1 to 1")));
+	result->value = asin(a->value);
+
+	/* check dimension */
+	for (i = 0; i < N_UNITS; i++)
+	{
+		if (a->units[i] != 0)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_ARGUMENT_FOR_POWER_FUNCTION),
+					 errmsg("cannot take asin of value that is not dimension-less")));
+		result->units[i] = 0;
+	}
+}
+
+void
+unit_tan_internal(Unit *a, Unit *result)
+{
+	int		 i;
+
+	/* compute tan of value */
+	result->value = tan(a->value);
+
+	/* check dimension */
+	for (i = 0; i < N_UNITS; i++)
+	{
+		if (a->units[i] != 0)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_ARGUMENT_FOR_POWER_FUNCTION),
+					 errmsg("cannot take tan of value that is not dimension-less")));
+		result->units[i] = 0;
+	}
+}
+
 /* obsolete version of unit_at_text used in v1..3 */
 /* needs search_path = @extschema@ due to use of unit_parse() */
 PG_FUNCTION_INFO_V1(unit_at);

unit.h

@@ -16,6 +16,16 @@
 
 #define N_UNITS		8
 
+/* functions recognized in parser */
+enum parser_function {
+	FUNCTION_SQRT,
+	FUNCTION_EXP,
+	FUNCTION_LN,
+	FUNCTION_LOG2,
+	FUNCTION_ASIN,
+	FUNCTION_TAN,
+};
+
 /* defined units */
 
 #define UNIT_NAME_LENGTH 32
@@ -132,4 +142,22 @@ unit_div_internal (Unit *a, Unit *b, Unit *result)
 		result->units[i] = a->units[i] - b->units[i];
 }
 
+void
+unit_sqrt_internal(Unit *a, Unit *result);
+
+void
+unit_exp_internal(Unit *a, Unit *result);
+
+void
+unit_ln_internal(Unit *a, Unit *result);
+
+void
+unit_log2_internal(Unit *a, Unit *result);
+
+void
+unit_asin_internal(Unit *a, Unit *result);
+
+void
+unit_tan_internal(Unit *a, Unit *result);
+
 #endif /* _UNIT_H */

unitparse.l

@@ -84,6 +84,36 @@ SUPER_9     \xe2\x81\xb9
 	return DOUBLE;
 }
 
+sqrt {
+	yyunitlval.FUNCTION = FUNCTION_SQRT;
+	return FUNCTION;
+}
+
+exp {
+	yyunitlval.FUNCTION = FUNCTION_EXP;
+	return FUNCTION;
+}
+
+ln {
+	yyunitlval.FUNCTION = FUNCTION_LN;
+	return FUNCTION;
+}
+
+log2 {
+	yyunitlval.FUNCTION = FUNCTION_LOG2;
+	return FUNCTION;
+}
+
+asin {
+	yyunitlval.FUNCTION = FUNCTION_ASIN;
+	return FUNCTION;
+}
+
+tan {
+	yyunitlval.FUNCTION = FUNCTION_TAN;
+	return FUNCTION;
+}
+
 {TIME_R} { /* hh:mm:ss[.sss] */
 	char *colon;
 	yyunitlval.DOUBLE = TIME_HOUR * atoi(yytext); /* hh */