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diff --git a/.venv/lib/python3.12/site-packages/numpy/lib/arraypad.py b/.venv/lib/python3.12/site-packages/numpy/lib/arraypad.py new file mode 100644 index 00000000..b06a645d --- /dev/null +++ b/.venv/lib/python3.12/site-packages/numpy/lib/arraypad.py @@ -0,0 +1,882 @@ +""" +The arraypad module contains a group of functions to pad values onto the edges +of an n-dimensional array. + +""" +import numpy as np +from numpy.core.overrides import array_function_dispatch +from numpy.lib.index_tricks import ndindex + + +__all__ = ['pad'] + + +############################################################################### +# Private utility functions. + + +def _round_if_needed(arr, dtype): + """ + Rounds arr inplace if destination dtype is integer. + + Parameters + ---------- + arr : ndarray + Input array. + dtype : dtype + The dtype of the destination array. + """ + if np.issubdtype(dtype, np.integer): + arr.round(out=arr) + + +def _slice_at_axis(sl, axis): + """ + Construct tuple of slices to slice an array in the given dimension. + + Parameters + ---------- + sl : slice + The slice for the given dimension. + axis : int + The axis to which `sl` is applied. All other dimensions are left + "unsliced". + + Returns + ------- + sl : tuple of slices + A tuple with slices matching `shape` in length. + + Examples + -------- + >>> _slice_at_axis(slice(None, 3, -1), 1) + (slice(None, None, None), slice(None, 3, -1), (...,)) + """ + return (slice(None),) * axis + (sl,) + (...,) + + +def _view_roi(array, original_area_slice, axis): + """ + Get a view of the current region of interest during iterative padding. + + When padding multiple dimensions iteratively corner values are + unnecessarily overwritten multiple times. This function reduces the + working area for the first dimensions so that corners are excluded. + + Parameters + ---------- + array : ndarray + The array with the region of interest. + original_area_slice : tuple of slices + Denotes the area with original values of the unpadded array. + axis : int + The currently padded dimension assuming that `axis` is padded before + `axis` + 1. + + Returns + ------- + roi : ndarray + The region of interest of the original `array`. + """ + axis += 1 + sl = (slice(None),) * axis + original_area_slice[axis:] + return array[sl] + + +def _pad_simple(array, pad_width, fill_value=None): + """ + Pad array on all sides with either a single value or undefined values. + + Parameters + ---------- + array : ndarray + Array to grow. + pad_width : sequence of tuple[int, int] + Pad width on both sides for each dimension in `arr`. + fill_value : scalar, optional + If provided the padded area is filled with this value, otherwise + the pad area left undefined. + + Returns + ------- + padded : ndarray + The padded array with the same dtype as`array`. Its order will default + to C-style if `array` is not F-contiguous. + original_area_slice : tuple + A tuple of slices pointing to the area of the original array. + """ + # Allocate grown array + new_shape = tuple( + left + size + right + for size, (left, right) in zip(array.shape, pad_width) + ) + order = 'F' if array.flags.fnc else 'C' # Fortran and not also C-order + padded = np.empty(new_shape, dtype=array.dtype, order=order) + + if fill_value is not None: + padded.fill(fill_value) + + # Copy old array into correct space + original_area_slice = tuple( + slice(left, left + size) + for size, (left, right) in zip(array.shape, pad_width) + ) + padded[original_area_slice] = array + + return padded, original_area_slice + + +def _set_pad_area(padded, axis, width_pair, value_pair): + """ + Set empty-padded area in given dimension. + + Parameters + ---------- + padded : ndarray + Array with the pad area which is modified inplace. + axis : int + Dimension with the pad area to set. + width_pair : (int, int) + Pair of widths that mark the pad area on both sides in the given + dimension. + value_pair : tuple of scalars or ndarrays + Values inserted into the pad area on each side. It must match or be + broadcastable to the shape of `arr`. + """ + left_slice = _slice_at_axis(slice(None, width_pair[0]), axis) + padded[left_slice] = value_pair[0] + + right_slice = _slice_at_axis( + slice(padded.shape[axis] - width_pair[1], None), axis) + padded[right_slice] = value_pair[1] + + +def _get_edges(padded, axis, width_pair): + """ + Retrieve edge values from empty-padded array in given dimension. + + Parameters + ---------- + padded : ndarray + Empty-padded array. + axis : int + Dimension in which the edges are considered. + width_pair : (int, int) + Pair of widths that mark the pad area on both sides in the given + dimension. + + Returns + ------- + left_edge, right_edge : ndarray + Edge values of the valid area in `padded` in the given dimension. Its + shape will always match `padded` except for the dimension given by + `axis` which will have a length of 1. + """ + left_index = width_pair[0] + left_slice = _slice_at_axis(slice(left_index, left_index + 1), axis) + left_edge = padded[left_slice] + + right_index = padded.shape[axis] - width_pair[1] + right_slice = _slice_at_axis(slice(right_index - 1, right_index), axis) + right_edge = padded[right_slice] + + return left_edge, right_edge + + +def _get_linear_ramps(padded, axis, width_pair, end_value_pair): + """ + Construct linear ramps for empty-padded array in given dimension. + + Parameters + ---------- + padded : ndarray + Empty-padded array. + axis : int + Dimension in which the ramps are constructed. + width_pair : (int, int) + Pair of widths that mark the pad area on both sides in the given + dimension. + end_value_pair : (scalar, scalar) + End values for the linear ramps which form the edge of the fully padded + array. These values are included in the linear ramps. + + Returns + ------- + left_ramp, right_ramp : ndarray + Linear ramps to set on both sides of `padded`. + """ + edge_pair = _get_edges(padded, axis, width_pair) + + left_ramp, right_ramp = ( + np.linspace( + start=end_value, + stop=edge.squeeze(axis), # Dimension is replaced by linspace + num=width, + endpoint=False, + dtype=padded.dtype, + axis=axis + ) + for end_value, edge, width in zip( + end_value_pair, edge_pair, width_pair + ) + ) + + # Reverse linear space in appropriate dimension + right_ramp = right_ramp[_slice_at_axis(slice(None, None, -1), axis)] + + return left_ramp, right_ramp + + +def _get_stats(padded, axis, width_pair, length_pair, stat_func): + """ + Calculate statistic for the empty-padded array in given dimension. + + Parameters + ---------- + padded : ndarray + Empty-padded array. + axis : int + Dimension in which the statistic is calculated. + width_pair : (int, int) + Pair of widths that mark the pad area on both sides in the given + dimension. + length_pair : 2-element sequence of None or int + Gives the number of values in valid area from each side that is + taken into account when calculating the statistic. If None the entire + valid area in `padded` is considered. + stat_func : function + Function to compute statistic. The expected signature is + ``stat_func(x: ndarray, axis: int, keepdims: bool) -> ndarray``. + + Returns + ------- + left_stat, right_stat : ndarray + Calculated statistic for both sides of `padded`. + """ + # Calculate indices of the edges of the area with original values + left_index = width_pair[0] + right_index = padded.shape[axis] - width_pair[1] + # as well as its length + max_length = right_index - left_index + + # Limit stat_lengths to max_length + left_length, right_length = length_pair + if left_length is None or max_length < left_length: + left_length = max_length + if right_length is None or max_length < right_length: + right_length = max_length + + if (left_length == 0 or right_length == 0) \ + and stat_func in {np.amax, np.amin}: + # amax and amin can't operate on an empty array, + # raise a more descriptive warning here instead of the default one + raise ValueError("stat_length of 0 yields no value for padding") + + # Calculate statistic for the left side + left_slice = _slice_at_axis( + slice(left_index, left_index + left_length), axis) + left_chunk = padded[left_slice] + left_stat = stat_func(left_chunk, axis=axis, keepdims=True) + _round_if_needed(left_stat, padded.dtype) + + if left_length == right_length == max_length: + # return early as right_stat must be identical to left_stat + return left_stat, left_stat + + # Calculate statistic for the right side + right_slice = _slice_at_axis( + slice(right_index - right_length, right_index), axis) + right_chunk = padded[right_slice] + right_stat = stat_func(right_chunk, axis=axis, keepdims=True) + _round_if_needed(right_stat, padded.dtype) + + return left_stat, right_stat + + +def _set_reflect_both(padded, axis, width_pair, method, include_edge=False): + """ + Pad `axis` of `arr` with reflection. + + Parameters + ---------- + padded : ndarray + Input array of arbitrary shape. + axis : int + Axis along which to pad `arr`. + width_pair : (int, int) + Pair of widths that mark the pad area on both sides in the given + dimension. + method : str + Controls method of reflection; options are 'even' or 'odd'. + include_edge : bool + If true, edge value is included in reflection, otherwise the edge + value forms the symmetric axis to the reflection. + + Returns + ------- + pad_amt : tuple of ints, length 2 + New index positions of padding to do along the `axis`. If these are + both 0, padding is done in this dimension. + """ + left_pad, right_pad = width_pair + old_length = padded.shape[axis] - right_pad - left_pad + + if include_edge: + # Edge is included, we need to offset the pad amount by 1 + edge_offset = 1 + else: + edge_offset = 0 # Edge is not included, no need to offset pad amount + old_length -= 1 # but must be omitted from the chunk + + if left_pad > 0: + # Pad with reflected values on left side: + # First limit chunk size which can't be larger than pad area + chunk_length = min(old_length, left_pad) + # Slice right to left, stop on or next to edge, start relative to stop + stop = left_pad - edge_offset + start = stop + chunk_length + left_slice = _slice_at_axis(slice(start, stop, -1), axis) + left_chunk = padded[left_slice] + + if method == "odd": + # Negate chunk and align with edge + edge_slice = _slice_at_axis(slice(left_pad, left_pad + 1), axis) + left_chunk = 2 * padded[edge_slice] - left_chunk + + # Insert chunk into padded area + start = left_pad - chunk_length + stop = left_pad + pad_area = _slice_at_axis(slice(start, stop), axis) + padded[pad_area] = left_chunk + # Adjust pointer to left edge for next iteration + left_pad -= chunk_length + + if right_pad > 0: + # Pad with reflected values on right side: + # First limit chunk size which can't be larger than pad area + chunk_length = min(old_length, right_pad) + # Slice right to left, start on or next to edge, stop relative to start + start = -right_pad + edge_offset - 2 + stop = start - chunk_length + right_slice = _slice_at_axis(slice(start, stop, -1), axis) + right_chunk = padded[right_slice] + + if method == "odd": + # Negate chunk and align with edge + edge_slice = _slice_at_axis( + slice(-right_pad - 1, -right_pad), axis) + right_chunk = 2 * padded[edge_slice] - right_chunk + + # Insert chunk into padded area + start = padded.shape[axis] - right_pad + stop = start + chunk_length + pad_area = _slice_at_axis(slice(start, stop), axis) + padded[pad_area] = right_chunk + # Adjust pointer to right edge for next iteration + right_pad -= chunk_length + + return left_pad, right_pad + + +def _set_wrap_both(padded, axis, width_pair, original_period): + """ + Pad `axis` of `arr` with wrapped values. + + Parameters + ---------- + padded : ndarray + Input array of arbitrary shape. + axis : int + Axis along which to pad `arr`. + width_pair : (int, int) + Pair of widths that mark the pad area on both sides in the given + dimension. + original_period : int + Original length of data on `axis` of `arr`. + + Returns + ------- + pad_amt : tuple of ints, length 2 + New index positions of padding to do along the `axis`. If these are + both 0, padding is done in this dimension. + """ + left_pad, right_pad = width_pair + period = padded.shape[axis] - right_pad - left_pad + # Avoid wrapping with only a subset of the original area by ensuring period + # can only be a multiple of the original area's length. + period = period // original_period * original_period + + # If the current dimension of `arr` doesn't contain enough valid values + # (not part of the undefined pad area) we need to pad multiple times. + # Each time the pad area shrinks on both sides which is communicated with + # these variables. + new_left_pad = 0 + new_right_pad = 0 + + if left_pad > 0: + # Pad with wrapped values on left side + # First slice chunk from left side of the non-pad area. + # Use min(period, left_pad) to ensure that chunk is not larger than + # pad area. + slice_end = left_pad + period + slice_start = slice_end - min(period, left_pad) + right_slice = _slice_at_axis(slice(slice_start, slice_end), axis) + right_chunk = padded[right_slice] + + if left_pad > period: + # Chunk is smaller than pad area + pad_area = _slice_at_axis(slice(left_pad - period, left_pad), axis) + new_left_pad = left_pad - period + else: + # Chunk matches pad area + pad_area = _slice_at_axis(slice(None, left_pad), axis) + padded[pad_area] = right_chunk + + if right_pad > 0: + # Pad with wrapped values on right side + # First slice chunk from right side of the non-pad area. + # Use min(period, right_pad) to ensure that chunk is not larger than + # pad area. + slice_start = -right_pad - period + slice_end = slice_start + min(period, right_pad) + left_slice = _slice_at_axis(slice(slice_start, slice_end), axis) + left_chunk = padded[left_slice] + + if right_pad > period: + # Chunk is smaller than pad area + pad_area = _slice_at_axis( + slice(-right_pad, -right_pad + period), axis) + new_right_pad = right_pad - period + else: + # Chunk matches pad area + pad_area = _slice_at_axis(slice(-right_pad, None), axis) + padded[pad_area] = left_chunk + + return new_left_pad, new_right_pad + + +def _as_pairs(x, ndim, as_index=False): + """ + Broadcast `x` to an array with the shape (`ndim`, 2). + + A helper function for `pad` that prepares and validates arguments like + `pad_width` for iteration in pairs. + + Parameters + ---------- + x : {None, scalar, array-like} + The object to broadcast to the shape (`ndim`, 2). + ndim : int + Number of pairs the broadcasted `x` will have. + as_index : bool, optional + If `x` is not None, try to round each element of `x` to an integer + (dtype `np.intp`) and ensure every element is positive. + + Returns + ------- + pairs : nested iterables, shape (`ndim`, 2) + The broadcasted version of `x`. + + Raises + ------ + ValueError + If `as_index` is True and `x` contains negative elements. + Or if `x` is not broadcastable to the shape (`ndim`, 2). + """ + if x is None: + # Pass through None as a special case, otherwise np.round(x) fails + # with an AttributeError + return ((None, None),) * ndim + + x = np.array(x) + if as_index: + x = np.round(x).astype(np.intp, copy=False) + + if x.ndim < 3: + # Optimization: Possibly use faster paths for cases where `x` has + # only 1 or 2 elements. `np.broadcast_to` could handle these as well + # but is currently slower + + if x.size == 1: + # x was supplied as a single value + x = x.ravel() # Ensure x[0] works for x.ndim == 0, 1, 2 + if as_index and x < 0: + raise ValueError("index can't contain negative values") + return ((x[0], x[0]),) * ndim + + if x.size == 2 and x.shape != (2, 1): + # x was supplied with a single value for each side + # but except case when each dimension has a single value + # which should be broadcasted to a pair, + # e.g. [[1], [2]] -> [[1, 1], [2, 2]] not [[1, 2], [1, 2]] + x = x.ravel() # Ensure x[0], x[1] works + if as_index and (x[0] < 0 or x[1] < 0): + raise ValueError("index can't contain negative values") + return ((x[0], x[1]),) * ndim + + if as_index and x.min() < 0: + raise ValueError("index can't contain negative values") + + # Converting the array with `tolist` seems to improve performance + # when iterating and indexing the result (see usage in `pad`) + return np.broadcast_to(x, (ndim, 2)).tolist() + + +def _pad_dispatcher(array, pad_width, mode=None, **kwargs): + return (array,) + + +############################################################################### +# Public functions + + +@array_function_dispatch(_pad_dispatcher, module='numpy') +def pad(array, pad_width, mode='constant', **kwargs): + """ + Pad an array. + + Parameters + ---------- + array : array_like of rank N + The array to pad. + pad_width : {sequence, array_like, int} + Number of values padded to the edges of each axis. + ``((before_1, after_1), ... (before_N, after_N))`` unique pad widths + for each axis. + ``(before, after)`` or ``((before, after),)`` yields same before + and after pad for each axis. + ``(pad,)`` or ``int`` is a shortcut for before = after = pad width + for all axes. + mode : str or function, optional + One of the following string values or a user supplied function. + + 'constant' (default) + Pads with a constant value. + 'edge' + Pads with the edge values of array. + 'linear_ramp' + Pads with the linear ramp between end_value and the + array edge value. + 'maximum' + Pads with the maximum value of all or part of the + vector along each axis. + 'mean' + Pads with the mean value of all or part of the + vector along each axis. + 'median' + Pads with the median value of all or part of the + vector along each axis. + 'minimum' + Pads with the minimum value of all or part of the + vector along each axis. + 'reflect' + Pads with the reflection of the vector mirrored on + the first and last values of the vector along each + axis. + 'symmetric' + Pads with the reflection of the vector mirrored + along the edge of the array. + 'wrap' + Pads with the wrap of the vector along the axis. + The first values are used to pad the end and the + end values are used to pad the beginning. + 'empty' + Pads with undefined values. + + .. versionadded:: 1.17 + + <function> + Padding function, see Notes. + stat_length : sequence or int, optional + Used in 'maximum', 'mean', 'median', and 'minimum'. Number of + values at edge of each axis used to calculate the statistic value. + + ``((before_1, after_1), ... (before_N, after_N))`` unique statistic + lengths for each axis. + + ``(before, after)`` or ``((before, after),)`` yields same before + and after statistic lengths for each axis. + + ``(stat_length,)`` or ``int`` is a shortcut for + ``before = after = statistic`` length for all axes. + + Default is ``None``, to use the entire axis. + constant_values : sequence or scalar, optional + Used in 'constant'. The values to set the padded values for each + axis. + + ``((before_1, after_1), ... (before_N, after_N))`` unique pad constants + for each axis. + + ``(before, after)`` or ``((before, after),)`` yields same before + and after constants for each axis. + + ``(constant,)`` or ``constant`` is a shortcut for + ``before = after = constant`` for all axes. + + Default is 0. + end_values : sequence or scalar, optional + Used in 'linear_ramp'. The values used for the ending value of the + linear_ramp and that will form the edge of the padded array. + + ``((before_1, after_1), ... (before_N, after_N))`` unique end values + for each axis. + + ``(before, after)`` or ``((before, after),)`` yields same before + and after end values for each axis. + + ``(constant,)`` or ``constant`` is a shortcut for + ``before = after = constant`` for all axes. + + Default is 0. + reflect_type : {'even', 'odd'}, optional + Used in 'reflect', and 'symmetric'. The 'even' style is the + default with an unaltered reflection around the edge value. For + the 'odd' style, the extended part of the array is created by + subtracting the reflected values from two times the edge value. + + Returns + ------- + pad : ndarray + Padded array of rank equal to `array` with shape increased + according to `pad_width`. + + Notes + ----- + .. versionadded:: 1.7.0 + + For an array with rank greater than 1, some of the padding of later + axes is calculated from padding of previous axes. This is easiest to + think about with a rank 2 array where the corners of the padded array + are calculated by using padded values from the first axis. + + The padding function, if used, should modify a rank 1 array in-place. It + has the following signature:: + + padding_func(vector, iaxis_pad_width, iaxis, kwargs) + + where + + vector : ndarray + A rank 1 array already padded with zeros. Padded values are + vector[:iaxis_pad_width[0]] and vector[-iaxis_pad_width[1]:]. + iaxis_pad_width : tuple + A 2-tuple of ints, iaxis_pad_width[0] represents the number of + values padded at the beginning of vector where + iaxis_pad_width[1] represents the number of values padded at + the end of vector. + iaxis : int + The axis currently being calculated. + kwargs : dict + Any keyword arguments the function requires. + + Examples + -------- + >>> a = [1, 2, 3, 4, 5] + >>> np.pad(a, (2, 3), 'constant', constant_values=(4, 6)) + array([4, 4, 1, ..., 6, 6, 6]) + + >>> np.pad(a, (2, 3), 'edge') + array([1, 1, 1, ..., 5, 5, 5]) + + >>> np.pad(a, (2, 3), 'linear_ramp', end_values=(5, -4)) + array([ 5, 3, 1, 2, 3, 4, 5, 2, -1, -4]) + + >>> np.pad(a, (2,), 'maximum') + array([5, 5, 1, 2, 3, 4, 5, 5, 5]) + + >>> np.pad(a, (2,), 'mean') + array([3, 3, 1, 2, 3, 4, 5, 3, 3]) + + >>> np.pad(a, (2,), 'median') + array([3, 3, 1, 2, 3, 4, 5, 3, 3]) + + >>> a = [[1, 2], [3, 4]] + >>> np.pad(a, ((3, 2), (2, 3)), 'minimum') + array([[1, 1, 1, 2, 1, 1, 1], + [1, 1, 1, 2, 1, 1, 1], + [1, 1, 1, 2, 1, 1, 1], + [1, 1, 1, 2, 1, 1, 1], + [3, 3, 3, 4, 3, 3, 3], + [1, 1, 1, 2, 1, 1, 1], + [1, 1, 1, 2, 1, 1, 1]]) + + >>> a = [1, 2, 3, 4, 5] + >>> np.pad(a, (2, 3), 'reflect') + array([3, 2, 1, 2, 3, 4, 5, 4, 3, 2]) + + >>> np.pad(a, (2, 3), 'reflect', reflect_type='odd') + array([-1, 0, 1, 2, 3, 4, 5, 6, 7, 8]) + + >>> np.pad(a, (2, 3), 'symmetric') + array([2, 1, 1, 2, 3, 4, 5, 5, 4, 3]) + + >>> np.pad(a, (2, 3), 'symmetric', reflect_type='odd') + array([0, 1, 1, 2, 3, 4, 5, 5, 6, 7]) + + >>> np.pad(a, (2, 3), 'wrap') + array([4, 5, 1, 2, 3, 4, 5, 1, 2, 3]) + + >>> def pad_with(vector, pad_width, iaxis, kwargs): + ... pad_value = kwargs.get('padder', 10) + ... vector[:pad_width[0]] = pad_value + ... vector[-pad_width[1]:] = pad_value + >>> a = np.arange(6) + >>> a = a.reshape((2, 3)) + >>> np.pad(a, 2, pad_with) + array([[10, 10, 10, 10, 10, 10, 10], + [10, 10, 10, 10, 10, 10, 10], + [10, 10, 0, 1, 2, 10, 10], + [10, 10, 3, 4, 5, 10, 10], + [10, 10, 10, 10, 10, 10, 10], + [10, 10, 10, 10, 10, 10, 10]]) + >>> np.pad(a, 2, pad_with, padder=100) + array([[100, 100, 100, 100, 100, 100, 100], + [100, 100, 100, 100, 100, 100, 100], + [100, 100, 0, 1, 2, 100, 100], + [100, 100, 3, 4, 5, 100, 100], + [100, 100, 100, 100, 100, 100, 100], + [100, 100, 100, 100, 100, 100, 100]]) + """ + array = np.asarray(array) + pad_width = np.asarray(pad_width) + + if not pad_width.dtype.kind == 'i': + raise TypeError('`pad_width` must be of integral type.') + + # Broadcast to shape (array.ndim, 2) + pad_width = _as_pairs(pad_width, array.ndim, as_index=True) + + if callable(mode): + # Old behavior: Use user-supplied function with np.apply_along_axis + function = mode + # Create a new zero padded array + padded, _ = _pad_simple(array, pad_width, fill_value=0) + # And apply along each axis + + for axis in range(padded.ndim): + # Iterate using ndindex as in apply_along_axis, but assuming that + # function operates inplace on the padded array. + + # view with the iteration axis at the end + view = np.moveaxis(padded, axis, -1) + + # compute indices for the iteration axes, and append a trailing + # ellipsis to prevent 0d arrays decaying to scalars (gh-8642) + inds = ndindex(view.shape[:-1]) + inds = (ind + (Ellipsis,) for ind in inds) + for ind in inds: + function(view[ind], pad_width[axis], axis, kwargs) + + return padded + + # Make sure that no unsupported keywords were passed for the current mode + allowed_kwargs = { + 'empty': [], 'edge': [], 'wrap': [], + 'constant': ['constant_values'], + 'linear_ramp': ['end_values'], + 'maximum': ['stat_length'], + 'mean': ['stat_length'], + 'median': ['stat_length'], + 'minimum': ['stat_length'], + 'reflect': ['reflect_type'], + 'symmetric': ['reflect_type'], + } + try: + unsupported_kwargs = set(kwargs) - set(allowed_kwargs[mode]) + except KeyError: + raise ValueError("mode '{}' is not supported".format(mode)) from None + if unsupported_kwargs: + raise ValueError("unsupported keyword arguments for mode '{}': {}" + .format(mode, unsupported_kwargs)) + + stat_functions = {"maximum": np.amax, "minimum": np.amin, + "mean": np.mean, "median": np.median} + + # Create array with final shape and original values + # (padded area is undefined) + padded, original_area_slice = _pad_simple(array, pad_width) + # And prepare iteration over all dimensions + # (zipping may be more readable than using enumerate) + axes = range(padded.ndim) + + if mode == "constant": + values = kwargs.get("constant_values", 0) + values = _as_pairs(values, padded.ndim) + for axis, width_pair, value_pair in zip(axes, pad_width, values): + roi = _view_roi(padded, original_area_slice, axis) + _set_pad_area(roi, axis, width_pair, value_pair) + + elif mode == "empty": + pass # Do nothing as _pad_simple already returned the correct result + + elif array.size == 0: + # Only modes "constant" and "empty" can extend empty axes, all other + # modes depend on `array` not being empty + # -> ensure every empty axis is only "padded with 0" + for axis, width_pair in zip(axes, pad_width): + if array.shape[axis] == 0 and any(width_pair): + raise ValueError( + "can't extend empty axis {} using modes other than " + "'constant' or 'empty'".format(axis) + ) + # passed, don't need to do anything more as _pad_simple already + # returned the correct result + + elif mode == "edge": + for axis, width_pair in zip(axes, pad_width): + roi = _view_roi(padded, original_area_slice, axis) + edge_pair = _get_edges(roi, axis, width_pair) + _set_pad_area(roi, axis, width_pair, edge_pair) + + elif mode == "linear_ramp": + end_values = kwargs.get("end_values", 0) + end_values = _as_pairs(end_values, padded.ndim) + for axis, width_pair, value_pair in zip(axes, pad_width, end_values): + roi = _view_roi(padded, original_area_slice, axis) + ramp_pair = _get_linear_ramps(roi, axis, width_pair, value_pair) + _set_pad_area(roi, axis, width_pair, ramp_pair) + + elif mode in stat_functions: + func = stat_functions[mode] + length = kwargs.get("stat_length", None) + length = _as_pairs(length, padded.ndim, as_index=True) + for axis, width_pair, length_pair in zip(axes, pad_width, length): + roi = _view_roi(padded, original_area_slice, axis) + stat_pair = _get_stats(roi, axis, width_pair, length_pair, func) + _set_pad_area(roi, axis, width_pair, stat_pair) + + elif mode in {"reflect", "symmetric"}: + method = kwargs.get("reflect_type", "even") + include_edge = True if mode == "symmetric" else False + for axis, (left_index, right_index) in zip(axes, pad_width): + if array.shape[axis] == 1 and (left_index > 0 or right_index > 0): + # Extending singleton dimension for 'reflect' is legacy + # behavior; it really should raise an error. + edge_pair = _get_edges(padded, axis, (left_index, right_index)) + _set_pad_area( + padded, axis, (left_index, right_index), edge_pair) + continue + + roi = _view_roi(padded, original_area_slice, axis) + while left_index > 0 or right_index > 0: + # Iteratively pad until dimension is filled with reflected + # values. This is necessary if the pad area is larger than + # the length of the original values in the current dimension. + left_index, right_index = _set_reflect_both( + roi, axis, (left_index, right_index), + method, include_edge + ) + + elif mode == "wrap": + for axis, (left_index, right_index) in zip(axes, pad_width): + roi = _view_roi(padded, original_area_slice, axis) + original_period = padded.shape[axis] - right_index - left_index + while left_index > 0 or right_index > 0: + # Iteratively pad until dimension is filled with wrapped + # values. This is necessary if the pad area is larger than + # the length of the original values in the current dimension. + left_index, right_index = _set_wrap_both( + roi, axis, (left_index, right_index), original_period) + + return padded |