django.db.models.functions.math のソースコード
import math
from django.db.models.expressions import Func
from django.db.models.fields import FloatField, IntegerField
from django.db.models.functions import Cast
from django.db.models.functions.mixins import (
FixDecimalInputMixin, NumericOutputFieldMixin,
)
from django.db.models.lookups import Transform
[ドキュメント]class ATan2(NumericOutputFieldMixin, Func):
function = 'ATAN2'
arity = 2
def as_sqlite(self, compiler, connection, **extra_context):
if not getattr(connection.ops, 'spatialite', False) or not (
(4, 3, 0) <= connection.ops.spatial_version < (5, 0, 0)
):
return self.as_sql(compiler, connection)
# This function is usually ATan2(y, x), returning the inverse tangent
# of y / x, but it's ATan2(x, y) on SpatiaLite >= 4.3.0, < 5.0.0.
# Cast integers to float to avoid inconsistent/buggy behavior if the
# arguments are mixed between integer and float or decimal.
# https://www.gaia-gis.it/fossil/libspatialite/tktview?name=0f72cca3a2
clone = self.copy()
clone.set_source_expressions([
Cast(expression, FloatField()) if isinstance(expression.output_field, IntegerField)
else expression for expression in self.get_source_expressions()[::-1]
])
return clone.as_sql(compiler, connection, **extra_context)
[ドキュメント]class Ceil(Transform):
function = 'CEILING'
lookup_name = 'ceil'
def as_oracle(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, function='CEIL', **extra_context)
[ドキュメント]class Cot(NumericOutputFieldMixin, Transform):
function = 'COT'
lookup_name = 'cot'
def as_oracle(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, template='(1 / TAN(%(expressions)s))', **extra_context)
[ドキュメント]class Degrees(NumericOutputFieldMixin, Transform):
function = 'DEGREES'
lookup_name = 'degrees'
def as_oracle(self, compiler, connection, **extra_context):
return super().as_sql(
compiler, connection,
template='((%%(expressions)s) * 180 / %s)' % math.pi,
**extra_context
)
[ドキュメント]class Log(FixDecimalInputMixin, NumericOutputFieldMixin, Func):
function = 'LOG'
arity = 2
def as_sqlite(self, compiler, connection, **extra_context):
if not getattr(connection.ops, 'spatialite', False):
return self.as_sql(compiler, connection)
# This function is usually Log(b, x) returning the logarithm of x to
# the base b, but on SpatiaLite it's Log(x, b).
clone = self.copy()
clone.set_source_expressions(self.get_source_expressions()[::-1])
return clone.as_sql(compiler, connection, **extra_context)
[ドキュメント]class Pi(NumericOutputFieldMixin, Func):
function = 'PI'
arity = 0
def as_oracle(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, template=str(math.pi), **extra_context)
[ドキュメント]class Radians(NumericOutputFieldMixin, Transform):
function = 'RADIANS'
lookup_name = 'radians'
def as_oracle(self, compiler, connection, **extra_context):
return super().as_sql(
compiler, connection,
template='((%%(expressions)s) * %s / 180)' % math.pi,
**extra_context
)