""" For compatibility with numpy libraries, pandas functions or methods have to accept '*args' and '**kwargs' parameters to accommodate numpy arguments that are not actually used or respected in the pandas implementation. To ensure that users do not abuse these parameters, validation is performed in 'validators.py' to make sure that any extra parameters passed correspond ONLY to those in the numpy signature. Part of that validation includes whether or not the user attempted to pass in non-default values for these extraneous parameters. As we want to discourage users from relying on these parameters when calling the pandas implementation, we want them only to pass in the default values for these parameters. This module provides a set of commonly used default arguments for functions and methods that are spread throughout the codebase. This module will make it easier to adjust to future upstream changes in the analogous numpy signatures. """ from numpy import ndarray from pandas.util._validators import (validate_args, validate_kwargs, validate_args_and_kwargs) from pandas.errors import UnsupportedFunctionCall from pandas.core.dtypes.common import is_integer, is_bool from pandas.compat import OrderedDict class CompatValidator(object): def __init__(self, defaults, fname=None, method=None, max_fname_arg_count=None): self.fname = fname self.method = method self.defaults = defaults self.max_fname_arg_count = max_fname_arg_count def __call__(self, args, kwargs, fname=None, max_fname_arg_count=None, method=None): if args or kwargs: fname = self.fname if fname is None else fname max_fname_arg_count = (self.max_fname_arg_count if max_fname_arg_count is None else max_fname_arg_count) method = self.method if method is None else method if method == 'args': validate_args(fname, args, max_fname_arg_count, self.defaults) elif method == 'kwargs': validate_kwargs(fname, kwargs, self.defaults) elif method == 'both': validate_args_and_kwargs(fname, args, kwargs, max_fname_arg_count, self.defaults) else: raise ValueError("invalid validation method " "'{method}'".format(method=method)) ARGMINMAX_DEFAULTS = dict(out=None) validate_argmin = CompatValidator(ARGMINMAX_DEFAULTS, fname='argmin', method='both', max_fname_arg_count=1) validate_argmax = CompatValidator(ARGMINMAX_DEFAULTS, fname='argmax', method='both', max_fname_arg_count=1) def process_skipna(skipna, args): if isinstance(skipna, ndarray) or skipna is None: args = (skipna,) + args skipna = True return skipna, args def validate_argmin_with_skipna(skipna, args, kwargs): """ If 'Series.argmin' is called via the 'numpy' library, the third parameter in its signature is 'out', which takes either an ndarray or 'None', so check if the 'skipna' parameter is either an instance of ndarray or is None, since 'skipna' itself should be a boolean """ skipna, args = process_skipna(skipna, args) validate_argmin(args, kwargs) return skipna def validate_argmax_with_skipna(skipna, args, kwargs): """ If 'Series.argmax' is called via the 'numpy' library, the third parameter in its signature is 'out', which takes either an ndarray or 'None', so check if the 'skipna' parameter is either an instance of ndarray or is None, since 'skipna' itself should be a boolean """ skipna, args = process_skipna(skipna, args) validate_argmax(args, kwargs) return skipna ARGSORT_DEFAULTS = OrderedDict() ARGSORT_DEFAULTS['axis'] = -1 ARGSORT_DEFAULTS['kind'] = 'quicksort' ARGSORT_DEFAULTS['order'] = None validate_argsort = CompatValidator(ARGSORT_DEFAULTS, fname='argsort', max_fname_arg_count=0, method='both') # two different signatures of argsort, this second validation # for when the `kind` param is supported ARGSORT_DEFAULTS_KIND = OrderedDict() ARGSORT_DEFAULTS_KIND['axis'] = -1 ARGSORT_DEFAULTS_KIND['order'] = None validate_argsort_kind = CompatValidator(ARGSORT_DEFAULTS_KIND, fname='argsort', max_fname_arg_count=0, method='both') def validate_argsort_with_ascending(ascending, args, kwargs): """ If 'Categorical.argsort' is called via the 'numpy' library, the first parameter in its signature is 'axis', which takes either an integer or 'None', so check if the 'ascending' parameter has either integer type or is None, since 'ascending' itself should be a boolean """ if is_integer(ascending) or ascending is None: args = (ascending,) + args ascending = True validate_argsort_kind(args, kwargs, max_fname_arg_count=3) return ascending CLIP_DEFAULTS = dict(out=None) validate_clip = CompatValidator(CLIP_DEFAULTS, fname='clip', method='both', max_fname_arg_count=3) def validate_clip_with_axis(axis, args, kwargs): """ If 'NDFrame.clip' is called via the numpy library, the third parameter in its signature is 'out', which can takes an ndarray, so check if the 'axis' parameter is an instance of ndarray, since 'axis' itself should either be an integer or None """ if isinstance(axis, ndarray): args = (axis,) + args axis = None validate_clip(args, kwargs) return axis COMPRESS_DEFAULTS = OrderedDict() COMPRESS_DEFAULTS['axis'] = None COMPRESS_DEFAULTS['out'] = None validate_compress = CompatValidator(COMPRESS_DEFAULTS, fname='compress', method='both', max_fname_arg_count=1) CUM_FUNC_DEFAULTS = OrderedDict() CUM_FUNC_DEFAULTS['dtype'] = None CUM_FUNC_DEFAULTS['out'] = None validate_cum_func = CompatValidator(CUM_FUNC_DEFAULTS, method='both', max_fname_arg_count=1) validate_cumsum = CompatValidator(CUM_FUNC_DEFAULTS, fname='cumsum', method='both', max_fname_arg_count=1) def validate_cum_func_with_skipna(skipna, args, kwargs, name): """ If this function is called via the 'numpy' library, the third parameter in its signature is 'dtype', which takes either a 'numpy' dtype or 'None', so check if the 'skipna' parameter is a boolean or not """ if not is_bool(skipna): args = (skipna,) + args skipna = True validate_cum_func(args, kwargs, fname=name) return skipna ALLANY_DEFAULTS = OrderedDict() ALLANY_DEFAULTS['dtype'] = None ALLANY_DEFAULTS['out'] = None validate_all = CompatValidator(ALLANY_DEFAULTS, fname='all', method='both', max_fname_arg_count=1) validate_any = CompatValidator(ALLANY_DEFAULTS, fname='any', method='both', max_fname_arg_count=1) LOGICAL_FUNC_DEFAULTS = dict(out=None) validate_logical_func = CompatValidator(LOGICAL_FUNC_DEFAULTS, method='kwargs') MINMAX_DEFAULTS = dict(out=None) validate_min = CompatValidator(MINMAX_DEFAULTS, fname='min', method='both', max_fname_arg_count=1) validate_max = CompatValidator(MINMAX_DEFAULTS, fname='max', method='both', max_fname_arg_count=1) RESHAPE_DEFAULTS = dict(order='C') validate_reshape = CompatValidator(RESHAPE_DEFAULTS, fname='reshape', method='both', max_fname_arg_count=1) REPEAT_DEFAULTS = dict(axis=None) validate_repeat = CompatValidator(REPEAT_DEFAULTS, fname='repeat', method='both', max_fname_arg_count=1) ROUND_DEFAULTS = dict(out=None) validate_round = CompatValidator(ROUND_DEFAULTS, fname='round', method='both', max_fname_arg_count=1) SORT_DEFAULTS = OrderedDict() SORT_DEFAULTS['axis'] = -1 SORT_DEFAULTS['kind'] = 'quicksort' SORT_DEFAULTS['order'] = None validate_sort = CompatValidator(SORT_DEFAULTS, fname='sort', method='kwargs') STAT_FUNC_DEFAULTS = OrderedDict() STAT_FUNC_DEFAULTS['dtype'] = None STAT_FUNC_DEFAULTS['out'] = None validate_stat_func = CompatValidator(STAT_FUNC_DEFAULTS, method='kwargs') validate_sum = CompatValidator(STAT_FUNC_DEFAULTS, fname='sort', method='both', max_fname_arg_count=1) validate_mean = CompatValidator(STAT_FUNC_DEFAULTS, fname='mean', method='both', max_fname_arg_count=1) STAT_DDOF_FUNC_DEFAULTS = OrderedDict() STAT_DDOF_FUNC_DEFAULTS['dtype'] = None STAT_DDOF_FUNC_DEFAULTS['out'] = None validate_stat_ddof_func = CompatValidator(STAT_DDOF_FUNC_DEFAULTS, method='kwargs') TAKE_DEFAULTS = OrderedDict() TAKE_DEFAULTS['out'] = None TAKE_DEFAULTS['mode'] = 'raise' validate_take = CompatValidator(TAKE_DEFAULTS, fname='take', method='kwargs') def validate_take_with_convert(convert, args, kwargs): """ If this function is called via the 'numpy' library, the third parameter in its signature is 'axis', which takes either an ndarray or 'None', so check if the 'convert' parameter is either an instance of ndarray or is None """ if isinstance(convert, ndarray) or convert is None: args = (convert,) + args convert = True validate_take(args, kwargs, max_fname_arg_count=3, method='both') return convert TRANSPOSE_DEFAULTS = dict(axes=None) validate_transpose = CompatValidator(TRANSPOSE_DEFAULTS, fname='transpose', method='both', max_fname_arg_count=0) def validate_transpose_for_generic(inst, kwargs): try: validate_transpose(tuple(), kwargs) except ValueError as e: klass = type(inst).__name__ msg = str(e) # the Panel class actual relies on the 'axes' parameter if called # via the 'numpy' library, so let's make sure the error is specific # about saying that the parameter is not supported for particular # implementations of 'transpose' if "the 'axes' parameter is not supported" in msg: msg += " for {klass} instances".format(klass=klass) raise ValueError(msg) def validate_window_func(name, args, kwargs): numpy_args = ('axis', 'dtype', 'out') msg = ("numpy operations are not " "valid with window objects. " "Use .{func}() directly instead ".format(func=name)) if len(args) > 0: raise UnsupportedFunctionCall(msg) for arg in numpy_args: if arg in kwargs: raise UnsupportedFunctionCall(msg) def validate_rolling_func(name, args, kwargs): numpy_args = ('axis', 'dtype', 'out') msg = ("numpy operations are not " "valid with window objects. " "Use .rolling(...).{func}() instead ".format(func=name)) if len(args) > 0: raise UnsupportedFunctionCall(msg) for arg in numpy_args: if arg in kwargs: raise UnsupportedFunctionCall(msg) def validate_expanding_func(name, args, kwargs): numpy_args = ('axis', 'dtype', 'out') msg = ("numpy operations are not " "valid with window objects. " "Use .expanding(...).{func}() instead ".format(func=name)) if len(args) > 0: raise UnsupportedFunctionCall(msg) for arg in numpy_args: if arg in kwargs: raise UnsupportedFunctionCall(msg) def validate_groupby_func(name, args, kwargs, allowed=None): """ 'args' and 'kwargs' should be empty, except for allowed kwargs because all of their necessary parameters are explicitly listed in the function signature """ if allowed is None: allowed = [] kwargs = set(kwargs) - set(allowed) if len(args) + len(kwargs) > 0: raise UnsupportedFunctionCall(( "numpy operations are not valid " "with groupby. Use .groupby(...)." "{func}() instead".format(func=name))) RESAMPLER_NUMPY_OPS = ('min', 'max', 'sum', 'prod', 'mean', 'std', 'var') def validate_resampler_func(method, args, kwargs): """ 'args' and 'kwargs' should be empty because all of their necessary parameters are explicitly listed in the function signature """ if len(args) + len(kwargs) > 0: if method in RESAMPLER_NUMPY_OPS: raise UnsupportedFunctionCall(( "numpy operations are not valid " "with resample. Use .resample(...)." "{func}() instead".format(func=method))) else: raise TypeError("too many arguments passed in")