in HowTo/gRPC/Linux/OpenAI/LangChain/PyServer/venv/Lib/numpy/lib/function_base.py [0:0]
def delete(arr, obj, axis=None):
"""
Return a new array with sub-arrays along an axis deleted. For a one
dimensional array, this returns those entries not returned by
`arr[obj]`.
Parameters
----------
arr : array_like
Input array.
obj : slice, int or array of ints
Indicate indices of sub-arrays to remove along the specified axis.
.. versionchanged:: 1.19.0
Boolean indices are now treated as a mask of elements to remove,
rather than being cast to the integers 0 and 1.
axis : int, optional
The axis along which to delete the subarray defined by `obj`.
If `axis` is None, `obj` is applied to the flattened array.
Returns
-------
out : ndarray
A copy of `arr` with the elements specified by `obj` removed. Note
that `delete` does not occur in-place. If `axis` is None, `out` is
a flattened array.
See Also
--------
insert : Insert elements into an array.
append : Append elements at the end of an array.
Notes
-----
Often it is preferable to use a boolean mask. For example:
>>> arr = np.arange(12) + 1
>>> mask = np.ones(len(arr), dtype=bool)
>>> mask[[0,2,4]] = False
>>> result = arr[mask,...]
Is equivalent to ``np.delete(arr, [0,2,4], axis=0)``, but allows further
use of `mask`.
Examples
--------
>>> arr = np.array([[1,2,3,4], [5,6,7,8], [9,10,11,12]])
>>> arr
array([[ 1, 2, 3, 4],
[ 5, 6, 7, 8],
[ 9, 10, 11, 12]])
>>> np.delete(arr, 1, 0)
array([[ 1, 2, 3, 4],
[ 9, 10, 11, 12]])
>>> np.delete(arr, np.s_[::2], 1)
array([[ 2, 4],
[ 6, 8],
[10, 12]])
>>> np.delete(arr, [1,3,5], None)
array([ 1, 3, 5, 7, 8, 9, 10, 11, 12])
"""
wrap = None
if type(arr) is not ndarray:
try:
wrap = arr.__array_wrap__
except AttributeError:
pass
arr = asarray(arr)
ndim = arr.ndim
arrorder = 'F' if arr.flags.fnc else 'C'
if axis is None:
if ndim != 1:
arr = arr.ravel()
# needed for np.matrix, which is still not 1d after being ravelled
ndim = arr.ndim
axis = ndim - 1
else:
axis = normalize_axis_index(axis, ndim)
slobj = [slice(None)]*ndim
N = arr.shape[axis]
newshape = list(arr.shape)
if isinstance(obj, slice):
start, stop, step = obj.indices(N)
xr = range(start, stop, step)
numtodel = len(xr)
if numtodel <= 0:
if wrap:
return wrap(arr.copy(order=arrorder))
else:
return arr.copy(order=arrorder)
# Invert if step is negative:
if step < 0:
step = -step
start = xr[-1]
stop = xr[0] + 1
newshape[axis] -= numtodel
new = empty(newshape, arr.dtype, arrorder)
# copy initial chunk
if start == 0:
pass
else:
slobj[axis] = slice(None, start)
new[tuple(slobj)] = arr[tuple(slobj)]
# copy end chunk
if stop == N:
pass
else:
slobj[axis] = slice(stop-numtodel, None)
slobj2 = [slice(None)]*ndim
slobj2[axis] = slice(stop, None)
new[tuple(slobj)] = arr[tuple(slobj2)]
# copy middle pieces
if step == 1:
pass
else: # use array indexing.
keep = ones(stop-start, dtype=bool)
keep[:stop-start:step] = False
slobj[axis] = slice(start, stop-numtodel)
slobj2 = [slice(None)]*ndim
slobj2[axis] = slice(start, stop)
arr = arr[tuple(slobj2)]
slobj2[axis] = keep
new[tuple(slobj)] = arr[tuple(slobj2)]
if wrap:
return wrap(new)
else:
return new
if isinstance(obj, (int, integer)) and not isinstance(obj, bool):
single_value = True
else:
single_value = False
_obj = obj
obj = np.asarray(obj)
# `size == 0` to allow empty lists similar to indexing, but (as there)
# is really too generic:
if obj.size == 0 and not isinstance(_obj, np.ndarray):
obj = obj.astype(intp)
elif obj.size == 1 and obj.dtype.kind in "ui":
# For a size 1 integer array we can use the single-value path
# (most dtypes, except boolean, should just fail later).
obj = obj.item()
single_value = True
if single_value:
# optimization for a single value
if (obj < -N or obj >= N):
raise IndexError(
"index %i is out of bounds for axis %i with "
"size %i" % (obj, axis, N))
if (obj < 0):
obj += N
newshape[axis] -= 1
new = empty(newshape, arr.dtype, arrorder)
slobj[axis] = slice(None, obj)
new[tuple(slobj)] = arr[tuple(slobj)]
slobj[axis] = slice(obj, None)
slobj2 = [slice(None)]*ndim
slobj2[axis] = slice(obj+1, None)
new[tuple(slobj)] = arr[tuple(slobj2)]
else:
if obj.dtype == bool:
if obj.shape != (N,):
raise ValueError('boolean array argument obj to delete '
'must be one dimensional and match the axis '
'length of {}'.format(N))
# optimization, the other branch is slower
keep = ~obj
else:
keep = ones(N, dtype=bool)
keep[obj,] = False
slobj[axis] = keep
new = arr[tuple(slobj)]
if wrap:
return wrap(new)
else:
return new