def wrapper_function(*args):
                arg_units = list(self._function._arg_units)

                if self._function.auto_vectorise:
                    arg_units += [DIMENSIONLESS]
                if not len(args) == len(arg_units):
                    raise ValueError(
                        ('Function %s got %d arguments, '
                         'expected %d') % (self._function.pyfunc.__name__,
                                           len(args), len(arg_units)))
                new_args = []
                for arg, arg_unit in zip(args, arg_units):
                    if arg_unit == bool or arg_unit is None or isinstance(
                            arg_unit, str):
                        new_args.append(arg)
                    else:
                        new_args.append(
                            Quantity.with_dimensions(arg,
                                                     get_dimensions(arg_unit)))
                result = orig_func(*new_args)
                if isinstance(self._function._return_unit, Callable):
                    return_unit = self._function._return_unit(
                        *[get_dimensions(a) for a in args])
                else:
                    return_unit = self._function._return_unit
                if return_unit == bool:
                    if not (isinstance(result, bool)
                            or np.asarray(result).dtype == bool):
                        raise TypeError('The function %s returned '
                                        '%s, but it was expected '
                                        'to return a boolean '
                                        'value ' %
                                        (orig_func.__name__, result))
                elif (isinstance(return_unit, int) and return_unit
                      == 1) or return_unit.dim is DIMENSIONLESS:
                    fail_for_dimension_mismatch(result,
                                                return_unit,
                                                'The function %s returned '
                                                '{value}, but it was expected '
                                                'to return a dimensionless '
                                                'quantity' %
                                                orig_func.__name__,
                                                value=result)
                else:
                    fail_for_dimension_mismatch(
                        result,
                        return_unit,
                        ('The function %s returned '
                         '{value}, but it was expected '
                         'to return a quantity with '
                         'units %r') % (orig_func.__name__, return_unit),
                        value=result)
                return np.asarray(result)
    def __init__(self,
                 type,
                 varname,
                 dimensions,
                 var_type=FLOAT,
                 expr=None,
                 flags=None):
        self.type = type
        self.varname = varname
        self.dim = get_dimensions(dimensions)
        self.var_type = var_type
        if dimensions is not DIMENSIONLESS:
            if var_type == BOOLEAN:
                raise TypeError(
                    'Boolean variables are necessarily dimensionless.')
            elif var_type == INTEGER:
                raise TypeError(
                    'Integer variables are necessarily dimensionless.')

        if type == DIFFERENTIAL_EQUATION:
            if var_type != FLOAT:
                raise TypeError(
                    'Differential equations can only define floating point variables'
                )
        self.expr = expr
        if flags is None:
            self.flags = []
        else:
            self.flags = list(flags)

        # will be set later in the sort_subexpressions method of Equations
        self.update_order = -1
Beispiel #3
0
    def __init__(self,
                 target,
                 target_var,
                 N,
                 rate,
                 weight,
                 when='synapses',
                 order=0):
        if target_var not in target.variables:
            raise KeyError('%s is not a variable of %s' %
                           (target_var, target.name))

        self._weight = weight
        self._target_var = target_var

        if isinstance(weight, str):
            weight = '(%s)' % weight
        else:
            weight_dims = get_dimensions(weight)
            target_dims = target.variables[target_var].dim
            # This will be checked automatically in the abstract code as well
            # but doing an explicit check here allows for a clearer error
            # message
            if not have_same_dimensions(weight_dims, target_dims):
                raise DimensionMismatchError(
                    ('The provided weight does not '
                     'have the same unit as the '
                     'target variable "%s"') % target_var, weight_dims,
                    target_dims)
            weight = repr(weight)
        self._N = N
        self._rate = rate
        binomial_sampling = BinomialFunction(N,
                                             rate * target.clock.dt,
                                             name='poissoninput_binomial*')

        code = '{targetvar} += {binomial}()*{weight}'.format(
            targetvar=target_var,
            binomial=binomial_sampling.name,
            weight=weight)
        self._stored_dt = target.dt_[:]  # make a copy
        # FIXME: we need an explicit reference here for on-the-fly subgroups
        # For example: PoissonInput(group[:N], ...)
        self._group = target
        CodeRunner.__init__(self,
                            group=target,
                            template='stateupdate',
                            code=code,
                            user_code='',
                            when=when,
                            order=order,
                            name='poissoninput*',
                            clock=target.clock)
        self.variables = Variables(self)
        self.variables._add_variable(binomial_sampling.name, binomial_sampling)
 def __init__(self, values, dt, name=None):
     if name is None:
         name = '_timedarray*'
     Nameable.__init__(self, name)
     dimensions = get_dimensions(values)
     self.dim = dimensions
     values = np.asarray(values, dtype=np.double)
     self.values = values
     dt = float(dt)
     self.dt = dt
     if values.ndim == 1:
         self._init_1d()
     elif values.ndim == 2:
         self._init_2d()
     else:
         raise NotImplementedError(('Only 1d and 2d arrays are supported '
                                    'for TimedArray'))
Beispiel #5
0
def check_units_statements(code, variables):
    '''
    Check the units for a series of statements. Setting a model variable has to
    use the correct unit. For newly introduced temporary variables, the unit
    is determined and used to check the following statements to ensure
    consistency.
    
    Parameters
    ----------
    code : str
        The statements as a (multi-line) string
    variables : dict of `Variable` objects
        The information about all variables used in `code` (including
        `Constant` objects for external variables)
    
    Raises
    ------
    KeyError
        In case on of the identifiers cannot be resolved.
    DimensionMismatchError
        If an unit mismatch occurs during the evaluation.
    '''
    variables = dict(variables)
    # Avoid a circular import
    from angela2.codegen.translation import analyse_identifiers
    newly_defined, _, unknown = analyse_identifiers(code, variables)

    if len(unknown):
        raise AssertionError(
            ('Encountered unknown identifiers, this should '
             'not happen at this stage. Unknown identifiers: %s' % unknown))

    code = re.split(r'[;\n]', code)
    for line in code:
        line = line.strip()
        if not len(line):
            continue  # skip empty lines

        varname, op, expr, comment = parse_statement(line)
        if op in ('+=', '-=', '*=', '/=', '%='):
            # Replace statements such as "w *=2" by "w = w * 2"
            expr = '{var} {op_first} {expr}'.format(var=varname,
                                                    op_first=op[0],
                                                    expr=expr)
            op = '='
        elif op == '=':
            pass
        else:
            raise AssertionError('Unknown operator "%s"' % op)

        expr_unit = parse_expression_dimensions(expr, variables)

        if varname in variables:
            expected_unit = variables[varname].dim
            fail_for_dimension_mismatch(expr_unit,
                                        expected_unit,
                                        ('The right-hand-side of code '
                                         'statement "%s" does not have the '
                                         'expected unit {expected}') % line,
                                        expected=expected_unit)
        elif varname in newly_defined:
            # note the unit for later
            variables[varname] = Variable(name=varname,
                                          dimensions=get_dimensions(expr_unit),
                                          scalar=False)
        else:
            raise AssertionError(('Variable "%s" is neither in the variables '
                                  'dictionary nor in the list of undefined '
                                  'variables.' % varname))
Beispiel #6
0
 def __init__(self, dimensions):
     self.dim = get_dimensions(dimensions)
def parse_expression_dimensions(expr, variables, orig_expr=None):
    '''
    Returns the unit value of an expression, and checks its validity
    
    Parameters
    ----------
    expr : str
        The expression to check.
    variables : dict
        Dictionary of all variables used in the `expr` (including `Constant`
        objects for external variables)
    
    Returns
    -------
    unit : Quantity
        The output unit of the expression
    
    Raises
    ------
    SyntaxError
        If the expression cannot be parsed, or if it uses ``a**b`` for ``b``
        anything other than a constant number.
    DimensionMismatchError
        If any part of the expression is dimensionally inconsistent.
    '''

    # If we are working on a string, convert to the top level node    
    if isinstance(expr, str):
        orig_expr = expr
        mod = ast.parse(expr, mode='eval')
        expr = mod.body
    if expr.__class__ is getattr(ast, 'NameConstant', None):
        # new class for True, False, None in Python 3.4
        value = expr.value
        if value is True or value is False:
            return DIMENSIONLESS
        else:
            raise ValueError('Do not know how to handle value %s' % value)
    if expr.__class__ is ast.Name:
        name = expr.id
        # Raise an error if a function is called as if it were a variable
        # (most of the time this happens for a TimedArray)
        if name in variables and isinstance(variables[name], Function):
            raise SyntaxError('%s was used like a variable/constant, but it is '
                              'a function.' % name,
                              ("<string>",
                               expr.lineno,
                               expr.col_offset + 1,
                               orig_expr)
                              )
        if name in variables:
            return get_dimensions(variables[name])
        elif name in ['True', 'False']:
            return DIMENSIONLESS
        else:
            raise KeyError('Unknown identifier %s' % name)
    elif (expr.__class__ is ast.Num or
          expr.__class__ is getattr(ast, 'Constant', None)):  # Python 3.8
        return DIMENSIONLESS
    elif expr.__class__ is ast.BoolOp:
        # check that the units are valid in each subexpression
        for node in expr.values:
            parse_expression_dimensions(node, variables, orig_expr=orig_expr)
        # but the result is a bool, so we just return 1 as the unit
        return DIMENSIONLESS
    elif expr.__class__ is ast.Compare:
        # check that the units are consistent in each subexpression
        subexprs = [expr.left]+expr.comparators
        subunits = []
        for node in subexprs:
            subunits.append(parse_expression_dimensions(node, variables, orig_expr=orig_expr))
        for left_dim, right_dim in zip(subunits[:-1], subunits[1:]):
            if not have_same_dimensions(left_dim, right_dim):
                msg = ('Comparison of expressions with different units. Expression '
                       '"{}" has unit ({}), while expression "{}" has units ({})').format(
                            NodeRenderer().render_node(expr.left), get_dimensions(left_dim),
                            NodeRenderer().render_node(expr.comparators[0]), get_dimensions(right_dim))
                raise DimensionMismatchError(msg)
        # but the result is a bool, so we just return 1 as the unit
        return DIMENSIONLESS
    elif expr.__class__ is ast.Call:
        if len(expr.keywords):
            raise ValueError("Keyword arguments not supported.")
        elif getattr(expr, 'starargs', None) is not None:
            raise ValueError("Variable number of arguments not supported")
        elif getattr(expr, 'kwargs', None) is not None:
            raise ValueError("Keyword arguments not supported")

        func = variables.get(expr.func.id, None)
        if func is None:
            raise SyntaxError('Unknown function %s' % expr.func.id,
                              ("<string>",
                               expr.lineno,
                               expr.col_offset + 1,
                               orig_expr)
                              )
        if not hasattr(func, '_arg_units') or not hasattr(func, '_return_unit'):
            raise ValueError(('Function %s does not specify how it '
                              'deals with units.') % expr.func.id)

        if len(func._arg_units) != len(expr.args):
            raise SyntaxError('Function %s was called with %d parameters, '
                              'needs %d.' % (expr.func.id,
                                             len(expr.args),
                                             len(func._arg_units)),
                              ("<string>",
                               expr.lineno,
                               expr.col_offset + len(expr.func.id) + 1,
                               orig_expr))



        for idx, (arg, expected_unit) in enumerate(zip(expr.args,
                                                       func._arg_units)):
            arg_unit = parse_expression_dimensions(arg, variables,
                                                   orig_expr=orig_expr)
            # A "None" in func._arg_units means: No matter what unit
            if expected_unit is None:
                continue
            # A string means: same unit as other argument
            elif isinstance(expected_unit, str):
                arg_idx = func._arg_names.index(expected_unit)
                expected_unit = parse_expression_dimensions(expr.args[arg_idx],
                                                              variables,
                                                              orig_expr=orig_expr)
                if not have_same_dimensions(arg_unit, expected_unit):
                    msg = (f'Argument number {idx + 1} for function '
                           f'{expr.func.id} was supposed to have the '
                           f'same units as argument number {arg_idx + 1}, but '
                           f'\'{NodeRenderer().render_node(arg)}\' has unit '
                           f'{get_unit_for_display(arg_unit)}, while '
                           f'\'{NodeRenderer().render_node(expr.args[arg_idx])}\' '
                           f'has unit {get_unit_for_display(expected_unit)}')
                    raise DimensionMismatchError(msg)
            elif expected_unit == bool:
                if not is_boolean_expression(arg, variables):
                    raise TypeError(('Argument number %d for function %s was '
                                     'expected to be a boolean value, but is '
                                     '"%s".') % (idx + 1, expr.func.id,
                                                 NodeRenderer().render_node(arg)))
            else:
                if not have_same_dimensions(arg_unit, expected_unit):
                    msg = ('Argument number {} for function {} does not have the '
                           'correct units. Expression "{}" has units ({}), but '
                           'should be ({}).').format(
                        idx+1, expr.func.id,
                        NodeRenderer().render_node(arg),
                        get_dimensions(arg_unit), get_dimensions(expected_unit))
                    raise DimensionMismatchError(msg)

        if func._return_unit == bool:
            return DIMENSIONLESS
        elif isinstance(func._return_unit, (Unit, int)):
            # Function always returns the same unit
            return getattr(func._return_unit, 'dim', DIMENSIONLESS)
        else:
            # Function returns a unit that depends on the arguments
            arg_units = [parse_expression_dimensions(arg, variables, orig_expr=orig_expr)
                         for arg in expr.args]
            return func._return_unit(*arg_units).dim

    elif expr.__class__ is ast.BinOp:
        op = expr.op.__class__.__name__
        left_dim = parse_expression_dimensions(expr.left, variables, orig_expr=orig_expr)
        right_dim = parse_expression_dimensions(expr.right, variables, orig_expr=orig_expr)
        if op in ['Add', 'Sub', 'Mod']:
            # dimensions should be the same
            if left_dim is not right_dim:
                op_symbol = {'Add': '+', 'Sub': '-', 'Mod': '%'}.get(op)
                left_str = NodeRenderer().render_node(expr.left)
                right_str = NodeRenderer().render_node(expr.right)
                left_unit = get_unit_for_display(left_dim)
                right_unit = get_unit_for_display(right_dim)
                error_msg = ('Expression "{left} {op} {right}" uses '
                             'inconsistent units ("{left}" has unit '
                             '{left_unit}; "{right}" '
                             'has unit {right_unit})').format(left=left_str,
                                                             right=right_str,
                                                             op=op_symbol,
                                                             left_unit=left_unit,
                                                             right_unit=right_unit)
                raise DimensionMismatchError(error_msg)
            u = left_dim
        elif op == 'Mult':
            u = left_dim*right_dim
        elif op == 'Div':
            u = left_dim/right_dim
        elif op == 'FloorDiv':
            if not (left_dim is DIMENSIONLESS and right_dim is DIMENSIONLESS):
                if left_dim is DIMENSIONLESS:
                    col_offset = expr.right.col_offset + 1
                else:
                    col_offset = expr.left.col_offset + 1
                raise SyntaxError('Floor division can only be used on '
                                  'dimensionless values.',
                                  ("<string>",
                                   expr.lineno,
                                   col_offset,
                                   orig_expr)
                                  )
            u = DIMENSIONLESS
        elif op == 'Pow':
            if left_dim is DIMENSIONLESS and right_dim is DIMENSIONLESS:
                return DIMENSIONLESS
            n = _get_value_from_expression(expr.right, variables)
            u = left_dim**n
        else:
            raise SyntaxError("Unsupported operation "+op,
                              ("<string>",
                               expr.lineno,
                               getattr(expr.left, 'end_col_offset',
                                       len(NodeRenderer().render_node(expr.left))) + 1,
                               orig_expr)
                              )
        return u
    elif expr.__class__ is ast.UnaryOp:
        op = expr.op.__class__.__name__
        # check validity of operand and get its unit
        u = parse_expression_dimensions(expr.operand, variables, orig_expr=orig_expr)
        if op == 'Not':
            return DIMENSIONLESS
        else:
            return u
    else:
        raise SyntaxError('Unsupported operation ' + str(expr.__class__.__name__),
                          ("<string>",
                           expr.lineno,
                           expr.col_offset + 1,
                           orig_expr)
                          )