Python ma.MaskedArray方法代码示例

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def get_size(item):
    """Return size of an item of arbitrary type"""
    if isinstance(item, (list, set, tuple, dict)):
        return len(item)
    elif isinstance(item, (ndarray, MaskedArray)):
        return item.shape
    elif isinstance(item, Image):
        return item.size
    if isinstance(item, (DataFrame, Index, Series)):
        try:
            return item.shape
        except RecursionError:
            # This is necessary to avoid an error when trying to
            # get the shape of these objects.
            # Fixes spyder-ide/spyder-kernels#217
            return (-1, -1)
    else:
        return 1 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def get_human_readable_type(item):
    """Return human-readable type string of an item"""
    if isinstance(item, (ndarray, MaskedArray)):
        return u'Array of ' + item.dtype.name
    elif isinstance(item, Image):
        return "Image"
    else:
        text = get_type_string(item)
        if text is None:
            text = to_text_string('Unknown')
        else:
            return text[text.find('.')+1:]


#==============================================================================
# Globals filter: filter namespace dictionaries (to be edited in
# CollectionsEditor)
#============================================================================== 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def transform_non_affine(self, points):
        if self._x.is_affine and self._y.is_affine:
            return points
        x = self._x
        y = self._y

        if x == y and x.input_dims == 2:
            return x.transform_non_affine(points)

        if x.input_dims == 2:
            x_points = x.transform_non_affine(points)[:, 0:1]
        else:
            x_points = x.transform_non_affine(points[:, 0])
            x_points = x_points.reshape((len(x_points), 1))

        if y.input_dims == 2:
            y_points = y.transform_non_affine(points)[:, 1:]
        else:
            y_points = y.transform_non_affine(points[:, 1])
            y_points = y_points.reshape((len(y_points), 1))

        if isinstance(x_points, MaskedArray) or isinstance(y_points, MaskedArray):
            return ma.concatenate((x_points, y_points), 1)
        else:
            return np.concatenate((x_points, y_points), 1) 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def view_field(self, name, type=None):
        """construct a view of one data field
        
        Parameters
        ----------
        name : string
            the name of the field
        type : type, optional
            the type of the returned array
        
        Returns
        -------
        view : MaskedArray
            a view of the specified field
        """
        view = self.data[name]
        
        if type is not None:
            return view.view(type=type)
        else:
            return view 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def hdmedian(data, axis=-1, var=False):
    """
    Returns the Harrell-Davis estimate of the median along the given axis.

    Parameters
    ----------
    data : ndarray
        Data array.
    axis : int, optional
        Axis along which to compute the quantiles. If None, use a flattened
        array.
    var : bool, optional
        Whether to return the variance of the estimate.

    Returns
    -------
    hdmedian : MaskedArray
        The median values.  If ``var=True``, the variance is returned inside
        the masked array.  E.g. for a 1-D array the shape change from (1,) to
        (2,).

    """
    result = hdquantiles(data,[0.5], axis=axis, var=var)
    return result.squeeze() 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def test_1D(self):
        a = (1,2,3,4)
        actual = mstats.gmean(a)
        desired = np.power(1*2*3*4,1./4.)
        assert_almost_equal(actual, desired, decimal=14)

        desired1 = mstats.gmean(a,axis=-1)
        assert_almost_equal(actual, desired1, decimal=14)
        assert_(not isinstance(desired1, ma.MaskedArray))

        a = ma.array((1,2,3,4),mask=(0,0,0,1))
        actual = mstats.gmean(a)
        desired = np.power(1*2*3,1./3.)
        assert_almost_equal(actual, desired,decimal=14)

        desired1 = mstats.gmean(a,axis=-1)
        assert_almost_equal(actual, desired1, decimal=14) 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def createFromMaskedArray(cls, masked_arr):
        """ Creates an ArrayWithMak

            :param masked_arr: a numpy MaskedArray or numpy array
            :return: ArrayWithMask
        """
        if isinstance(masked_arr, ArrayWithMask):
            return masked_arr

        check_class(masked_arr, (np.ndarray, ma.MaskedArray))

        # A MaskedConstant (i.e. masked) is a special case of MaskedArray. It does not seem to have
        # a fill_value so we use None to use the default.
        # https://docs.scipy.org/doc/numpy/reference/maskedarray.baseclass.html#numpy.ma.masked
        fill_value = getattr(masked_arr, 'fill_value', None)

        return cls(masked_arr.data, masked_arr.mask, fill_value) 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def fillValuesToNan(masked_array):
    """ Replaces the fill_values of the masked array by NaNs

        If the array is None or it does not contain floating point values, it cannot contain NaNs.
        In that case the original array is returned.
    """
    if masked_array is not None and masked_array.dtype.kind == 'f':
        check_class(masked_array, ma.masked_array)
        logger.debug("Replacing fill_values by NaNs")
        masked_array[:] = ma.filled(masked_array, np.nan)
        masked_array.set_fill_value(np.nan)
    else:
        return masked_array


#TODO: does recordMask help here?
# https://docs.scipy.org/doc/numpy/reference/maskedarray.baseclass.html#numpy.ma.MaskedArray.recordmask 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def _fix_output(output, usemask=True, asrecarray=False):
    """
    Private function: return a recarray, a ndarray, a MaskedArray
    or a MaskedRecords depending on the input parameters
    """
    if not isinstance(output, MaskedArray):
        usemask = False
    if usemask:
        if asrecarray:
            output = output.view(MaskedRecords)
    else:
        output = ma.filled(output)
        if asrecarray:
            output = output.view(recarray)
    return output 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def test_join_subdtype(self):
        # tests the bug in https://stackoverflow.com/q/44769632/102441
        from numpy.lib import recfunctions as rfn
        foo = np.array([(1,)],
                       dtype=[('key', int)])
        bar = np.array([(1, np.array([1,2,3]))],
                       dtype=[('key', int), ('value', 'uint16', 3)])
        res = join_by('key', foo, bar)
        assert_equal(res, bar.view(ma.MaskedArray)) 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def test_view_simple_dtype(self):
        (mrec, a, b, arr) = self.data
        ntype = (float, 2)
        test = mrec.view(ntype)
        assert_(isinstance(test, ma.MaskedArray))
        assert_equal(test, np.array(list(zip(a, b)), dtype=float))
        assert_(test[3, 1] is ma.masked) 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def argstoarray(*args):
    """
    Constructs a 2D array from a group of sequences.

    Sequences are filled with missing values to match the length of the longest
    sequence.

    Parameters
    ----------
    args : sequences
        Group of sequences.

    Returns
    -------
    argstoarray : MaskedArray
        A ( `m` x `n` ) masked array, where `m` is the number of arguments and
        `n` the length of the longest argument.

    Notes
    -----
    `numpy.ma.row_stack` has identical behavior, but is called with a sequence
    of sequences.

    """
    if len(args) == 1 and not isinstance(args[0], ndarray):
        output = ma.asarray(args[0])
        if output.ndim != 2:
            raise ValueError("The input should be 2D")
    else:
        n = len(args)
        m = max([len(k) for k in args])
        output = ma.array(np.empty((n,m), dtype=float), mask=True)
        for (k,v) in enumerate(args):
            output[k,:len(v)] = v

    output[np.logical_not(np.isfinite(output._data))] = masked
    return output 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def idealfourths(data, axis=None):
    """
    Returns an estimate of the lower and upper quartiles.

    Uses the ideal fourths algorithm.

    Parameters
    ----------
    data : array_like
        Input array.
    axis : int, optional
        Axis along which the quartiles are estimated. If None, the arrays are
        flattened.

    Returns
    -------
    idealfourths : {list of floats, masked array}
        Returns the two internal values that divide `data` into four parts
        using the ideal fourths algorithm either along the flattened array
        (if `axis` is None) or along `axis` of `data`.

    """
    def _idf(data):
        x = data.compressed()
        n = len(x)
        if n < 3:
            return [np.nan,np.nan]
        (j,h) = divmod(n/4. + 5/12.,1)
        j = int(j)
        qlo = (1-h)*x[j-1] + h*x[j]
        k = n - j
        qup = (1-h)*x[k] + h*x[k-1]
        return [qlo, qup]
    data = ma.sort(data, axis=axis).view(MaskedArray)
    if (axis is None):
        return _idf(data)
    else:
        return ma.apply_along_axis(_idf, axis, data) 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def test_view_simple_dtype(self):
        (mrec, a, b, arr) = self.data
        ntype = (np.float, 2)
        test = mrec.view(ntype)
        self.assertTrue(isinstance(test, ma.MaskedArray))
        assert_equal(test, np.array(list(zip(a, b)), dtype=np.float))
        self.assertTrue(test[3, 1] is ma.masked) 

# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import MaskedArray [as 别名]
def is_known_type(item):
    """Return True if object has a known type"""
    # Unfortunately, the masked array case is specific
    return isinstance(item, MaskedArray) or get_type_string(item) is not None