def testNodeTransformer(self):
from pyphant.core.AstTransformers import ReplaceName, ReplaceOperator, ReplaceCompare
rpn = ReplaceName(self.sampleContainer)
import ast
exprStr = 'col("i") / (col("t") + col("t"))'
expr = compile(exprStr, "<TestCase>", "eval", ast.PyCF_ONLY_AST)
replacedExpr = rpn.visit(expr)
print rpn.localDict
print ast.dump(replacedExpr)
rpc = ReplaceCompare(rpn.localDict)
factorExpr = rpc.visit(replacedExpr)
rpo = ReplaceOperator(rpn.localDict)
factorExpr = rpo.visit(factorExpr)
print ast.dump(factorExpr)
def calcColumn(self, exprStr, shortname, longname):
"""
Return an unsealed FieldContainer generated from `exprStr`.
Parameters
----------
exprStr : str
Expression has to be a string. Specifies the mathematical
operations which will be evaluated to generate a new FieldContainer
containing the result. `exprStr` may contain FieldContainers,
PhysicalQuantities, Booleans and Numbers as well as the operators
listed below.
shortname : str
The `shortname` of the returned FieldContainer.
longname : str
The `longname`of the returned FieldContainer.
Syntax
------
FieldContainer
FieldContainers can be adressed by their `shortname`or `longname`.
For a FieldContainer with shortname="exampleFC" the syntax within
`exprStr` is:
col("exampleFC")
where `col` stands for column and may be `Col` or `COL` as well.
Adressing by `longname` works analogously.
PhysicalQuantity
Within the expression PhysicalQuantities have to be enquoted:
"10kg", "100 m", "5 kg * m / s ** 2"
where the whitespaces are optional.
Booleans and Numbers
Can just be used without quotes or braces within `exprStr`:
True, False, 1.2, 10
Operators
---------
A list of all implemented operations that can be used within `exprStr`
sorted by precedence from lowest precedence (least binding) to highest
precedence (most binding):
or
and
not
Comparisons: <, <=, >, >=, <>, !=, ==
Addition and Subtraction: +, -
Multiplication, Division: *, /
Positive, Negative: +x, -x
Not implemented: ~, &, |, **, //, %, <<, >>
Examples
--------
Some examples of valid expressions will be given.
Data:
distance = FieldContainer(scipy.array([5., 10., 1.]),
Quantity('1.0 m'),
longname=u"Distance",
shortname=u"s")
time = FieldContainer(scipy.array([3., 4., 5.]),
Quantity('1.0 s'),
longname=u"Time",
shortname=u"t")
Examplary expressions:
exprStr = "col('Distance') / col('Time')"
exprStr = "col('Distance') - '1 m'"
exprStr = "col('t') >= '4 s'"
exprStr = "col('s') > '1 m' and COL('Time') == '3s'"
"""
exprStr = exprStr or "True"
import ast
rpn = ReplaceName(self)
expr = compile(exprStr, "<calcColumn>", "eval", ast.PyCF_ONLY_AST)
replacedExpr = rpn.visit(expr)
rpc = ReplaceCompare(rpn.localDict)
factorExpr = rpc.visit(replacedExpr)
rpo = ReplaceOperator(rpn.localDict)
factorExpr = rpo.visit(factorExpr)
localDict = dict([(key, value.data) for key, value in rpn.localDict.iteritems()])
numpyDict = {"logical_and": numpy.logical_and, "logical_or": numpy.logical_or, "logical_not": numpy.logical_not}
localDict.update(numpyDict)
data = eval(compile(factorExpr, "<calcColumn>", "eval"), {}, localDict)
unitcalc = UnitCalculator(rpn.localDict)
unit, dims = unitcalc.getUnitAndDim(replacedExpr)
if dims is None:
assert not isinstance(data, numpy.ndarray)
for col in self.columns:
checkDimensions(col.dimensions[0], self.columns[0].dimensions[0])
shape = self.columns[0].dimensions[0].data.shape
if data:
data = numpy.ones(shape, dtype=bool)
else:
data = numpy.zeros(shape, dtype=bool)
dims = [self.columns[0].dimensions[0]]
field = FieldContainer(data, unit, dimensions=dims, longname=longname, shortname=shortname)
return field
def calcColumn(self, exprStr, shortname, longname):
"""
Return an unsealed FieldContainer generated from `exprStr`.
Parameters
----------
exprStr : str
Expression has to be a string. Specifies the mathematical
operations which will be evaluated to generate a new FieldContainer
containing the result. `exprStr` may contain FieldContainers,
PhysicalQuantities, Booleans and Numbers as well as the operators
listed below.
shortname : str
The `shortname` of the returned FieldContainer.
longname : str
The `longname`of the returned FieldContainer.
Syntax
------
FieldContainer
FieldContainers can be adressed by their `shortname`or `longname`.
For a FieldContainer with shortname="exampleFC" the syntax within
`exprStr` is:
col("exampleFC")
where `col` stands for column and may be `Col` or `COL` as well.
Adressing by `longname` works analogously.
PhysicalQuantity
Within the expression PhysicalQuantities have to be enquoted:
"10kg", "100 m", "5 kg * m / s ** 2"
where the whitespaces are optional.
Booleans and Numbers
Can just be used without quotes or braces within `exprStr`:
True, False, 1.2, 10
Operators
---------
A list of all implemented operations that can be used within `exprStr`
sorted by precedence from lowest precedence (least binding) to highest
precedence (most binding):
or
and
not
Comparisons: <, <=, >, >=, <>, !=, ==
Addition and Subtraction: +, -
Multiplication, Division: *, /
Positive, Negative: +x, -x
Not implemented: ~, &, |, **, //, %, <<, >>
Examples
--------
Some examples of valid expressions will be given.
Data:
distance = FieldContainer(scipy.array([5., 10., 1.]),
Quantity('1.0 m'),
longname=u"Distance",
shortname=u"s")
time = FieldContainer(scipy.array([3., 4., 5.]),
Quantity('1.0 s'),
longname=u"Time",
shortname=u"t")
Examplary expressions:
exprStr = "col('Distance') / col('Time')"
exprStr = "col('Distance') - '1 m'"
exprStr = "col('t') >= '4 s'"
exprStr = "col('s') > '1 m' and COL('Time') == '3s'"
"""
exprStr = exprStr or 'True'
import ast
rpn = ReplaceName(self)
expr = compile(exprStr, "<calcColumn>", 'eval', ast.PyCF_ONLY_AST)
replacedExpr = rpn.visit(expr)
rpc = ReplaceCompare(rpn.localDict)
factorExpr = rpc.visit(replacedExpr)
rpo = ReplaceOperator(rpn.localDict)
factorExpr = rpo.visit(factorExpr)
localDict = dict([(key, value.data) \
for key, value in rpn.localDict.iteritems()])
numpyDict = {'logical_and':numpy.logical_and,
'logical_or':numpy.logical_or,
'logical_not':numpy.logical_not}
localDict.update(numpyDict)
data = eval(compile(factorExpr, '<calcColumn>', 'eval'), {}, localDict)
unitcalc = UnitCalculator(rpn.localDict)
unit, dims = unitcalc.getUnitAndDim(replacedExpr)
if dims is None:
assert not isinstance(data, numpy.ndarray)
for col in self.columns:
checkDimensions(col.dimensions[0],
self.columns[0].dimensions[0])
shape = self.columns[0].dimensions[0].data.shape
if data:
data = numpy.ones(shape, dtype=bool)
else:
data = numpy.zeros(shape, dtype=bool)
dims = [self.columns[0].dimensions[0]]
field = FieldContainer(data, unit, dimensions=dims,
longname=longname, shortname=shortname)
return field
