diff options
Diffstat (limited to 'numpy/core/fromnumeric.py')
| -rw-r--r-- | numpy/core/fromnumeric.py | 149 |
1 files changed, 118 insertions, 31 deletions
diff --git a/numpy/core/fromnumeric.py b/numpy/core/fromnumeric.py index 35c2e9a65..b0b186962 100644 --- a/numpy/core/fromnumeric.py +++ b/numpy/core/fromnumeric.py @@ -102,7 +102,7 @@ def reshape(a, newshape, order='C'): ------- reshaped_array : array This will be a new view object if possible; otherwise, it will - return a copy. + be a copy. See Also -------- @@ -194,10 +194,10 @@ def repeat(a, repeats, axis=None): See Also -------- ndarray.repeat : equivalent method + tile : tile an array Examples -------- - >>> repeat([0, 1, 2], 2) array([0, 0, 1, 1, 2, 2]) >>> repeat([0, 1, 2], [2, 3, 4]) @@ -222,6 +222,11 @@ def put(a, ind, v, mode='raise'): Target indices, interpreted as integers. v : array_like Values to place in `a` at target indices. + mode : {'raise', 'wrap', 'clip'}, optional + Specifies how out-of-bounds indices will behave. + 'raise' -- raise an error + 'wrap' -- wrap around + 'clip' -- clip to the range Notes ----- @@ -235,7 +240,6 @@ def put(a, ind, v, mode='raise'): Examples -------- - >>> x = np.arange(5) >>> np.put(x,[0,2,4],[-1,-2,-3]) >>> print x @@ -246,8 +250,8 @@ def put(a, ind, v, mode='raise'): def swapaxes(a, axis1, axis2): - """Return array a with axis1 and axis2 interchanged. - + """Return a view of array a with axis1 and axis2 interchanged. + Parameters ---------- a : array_like @@ -259,7 +263,6 @@ def swapaxes(a, axis1, axis2): Examples -------- - >>> x = np.array([[1,2,3]]) >>> np.swapaxes(x,0,1) array([[1], @@ -360,15 +363,13 @@ def sort(a, axis=-1, kind='quicksort', order=None): order. The three available algorithms have the following properties: - +-----------+-------+-------------+------------+-------+ - | kind | speed | worst case | work space | stable| - +===========+=======+=============+============+=======+ - | quicksort | 1 | O(n^2) | 0 | no | - +-----------+-------+-------------+------------+-------+ - | mergesort | 2 | O(n*log(n)) | ~n/2 | yes | - +-----------+-------+-------------+------------+-------+ - | heapsort | 3 | O(n*log(n)) | 0 | no | - +-----------+-------+-------------+------------+-------+ + =========== ======= ============= ============ ======= + kind speed worst case work space stable + =========== ======= ============= ============ ======= + 'quicksort' 1 O(n^2) 0 no + 'mergesort' 2 O(n*log(n)) ~n/2 yes + 'heapsort' 3 O(n*log(n)) 0 no + =========== ======= ============= ============ ======= All the sort algorithms make temporary copies of the data when the sort is not along the last axis. Consequently, sorts along @@ -705,8 +706,7 @@ def trace(a, offset=0, axis1=0, axis2=1, dtype=None, out=None): dimensions, then the axes specified by axis1 and axis2 are used to determine the 2-d subarray whose trace is returned. The shape of the resulting array can be determined by removing axis1 and axis2 and appending an index - to the right equal to the size of the resulting diagonals. Arrays of integer - type are summed + to the right equal to the size of the resulting diagonals. Parameters ---------- @@ -750,7 +750,7 @@ def trace(a, offset=0, axis1=0, axis2=1, dtype=None, out=None): return asarray(a).trace(offset, axis1, axis2, dtype, out) def ravel(a, order='C'): - """Return a 1d array containing the elements of a. + """Return a 1d array containing the elements of a (copy only if needed). Returns the elements of a as a 1d array. The elements in the new array are taken in the order specified by the order keyword. The new array is @@ -847,10 +847,38 @@ def shape(a): def compress(condition, a, axis=None, out=None): - """Return a where condition is true. + """Return selected slices of an array along given axis. - Equivalent to a[condition]. + Parameters + ---------- + condition : {array} + Boolean 1-d array selecting which entries to return. If len(condition) + is less than the size of a along the axis, then output is truncated + to length of condition array. + a : {array_type} + Array from which to extract a part. + axis : {None, integer} + Axis along which to take slices. If None, work on the flattened array. + out : array, optional + Output array. Its type is preserved and it must be of the right + shape to hold the output. + + Returns + ------- + compressed_array : array + A copy of a, without the slices along axis for which condition is false. + Examples + -------- + >>> a = np.array([[1, 2], [3, 4]]) + >>> np.compress([0, 1], a, axis=0) + array([[3, 4]]) + >>> np.compress([1], a, axis=1) + array([[1], + [3]]) + >>> np.compress([0,1,1], a) + array([2, 3]) + """ try: compress = a.compress @@ -860,11 +888,23 @@ def compress(condition, a, axis=None, out=None): def clip(a, a_min, a_max): - """Limit the values of a to [a_min, a_max]. Equivalent to + """Return an array whose values are limited to [a_min, a_max]. - a[a < a_min] = a_min - a[a > a_max] = a_max + Parameters + ---------- + a : {array_type} + Array containing elements to clip. + a_min + Minimum value + a_max + Maximum value + Returns + ------- + sum_along_axis : {array} + A new array whose elements are same as for a, but values + < a_min are replaced with a_min, and > a_max with a_max. + """ try: clip = a.clip @@ -874,7 +914,7 @@ def clip(a, a_min, a_max): def sum(a, axis=None, dtype=None, out=None): - """Sum the array over the given axis. + """Return the sum of the array elements over the given axis Parameters ---------- @@ -931,7 +971,7 @@ def sum(a, axis=None, dtype=None, out=None): def product (a, axis=None, dtype=None, out=None): - """Product of the array elements over the given axis. + """Return the product of the array elements over the given axis Parameters ---------- @@ -984,8 +1024,21 @@ def product (a, axis=None, dtype=None, out=None): def sometrue (a, axis=None, out=None): - """Perform a logical_or over the given axis. + """Check if any of the elements of `a` are true. + + Performs a logical_or over the given axis and returns the result + Parameters + ---------- + a : {array_like} + Array on which to operate + axis : {None, integer} + Axis to perform the operation over. + If None, perform over flattened array. + out : {None, array}, optional + Array into which the product can be placed. Its type is preserved + and it must be of the right shape to hold the output. + See Also -------- ndarray.any : equivalent method @@ -999,12 +1052,23 @@ def sometrue (a, axis=None, out=None): def alltrue (a, axis=None, out=None): - """Perform a logical_and over the given axis. + """Check if all of the elements of `a` are true. + + Performs a logical_and over the given axis and returns the result + Parameters + ---------- + a : {array_like} + axis : {None, integer} + Axis to perform the operation over. + If None, perform over flattened array. + out : {None, array}, optional + Array into which the product can be placed. Its type is preserved + and it must be of the right shape to hold the output. + See Also -------- ndarray.all : equivalent method - all : equivalent function """ try: @@ -1015,8 +1079,20 @@ def alltrue (a, axis=None, out=None): def any(a,axis=None, out=None): - """Return true if any elements of x are true. + """Check if any of the elements of `a` are true. + + Performs a logical_or over the given axis and returns the result + Parameters + ---------- + a : {array_like} + axis : {None, integer} + Axis to perform the operation over. + If None, perform over flattened array and return a scalar. + out : {None, array}, optional + Array into which the product can be placed. Its type is preserved + and it must be of the right shape to hold the output. + See Also -------- ndarray.any : equivalent method @@ -1030,12 +1106,23 @@ def any(a,axis=None, out=None): def all(a,axis=None, out=None): - """Return true if all elements of x are true: + """Check if all of the elements of `a` are true. + + Performs a logical_and over the given axis and returns the result + Parameters + ---------- + a : {array_like} + axis : {None, integer} + Axis to perform the operation over. + If None, perform over flattened array. + out : {None, array}, optional + Array into which the product can be placed. Its type is preserved + and it must be of the right shape to hold the output. + See Also -------- ndarray.all : equivalent method - alltrue : equivalent function """ try: |