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Indexing routines¶

Generating index arrays¶

`c_`	Translates slice objects to concatenation along the second axis.
`r_`	Translates slice objects to concatenation along the first axis.
`s_`	A nicer way to build up index tuples for arrays.
`nonzero` (a)	Return the indices of the elements that are non-zero.
`where` (condition, [x, y])	Return elements, either from x or y, depending on condition.
`indices` (dimensions[, dtype])	Return an array representing the indices of a grid.
`ix_` (*args)	Construct an open mesh from multiple sequences.
`ogrid`	Construct a multi-dimensional open “meshgrid”.
`unravel_index` (x, dims)	Convert a flat index into an index tuple for an array of given shape.

`take` (a, indices[, axis, out, mode])	Take elements from an array along an axis.
`choose` (a, choices[, out, mode])	Use an index array to construct a new array from a set of choices.
`compress` (condition, a[, axis, out])	Return selected slices of an array along given axis.
`diag` (v[, k])	Extract a diagonal or construct a diagonal array.
`diagonal` (a[, offset, axis1, axis2])	Return specified diagonals.
`select` (condlist, choicelist[, default])	Return an array drawn from elements in choicelist, depending on conditions.

`place` (arr, mask, vals)	Changes elements of an array based on conditional and input values.
`put` (a, ind, v[, mode])	Changes specific elements of one array by replacing from another array.
`putmask` (a, mask, values)	Changes elements of an array based on conditional and input values.

`ndenumerate`	Multidimensional index iterator.
`ndindex`	Pass in a sequence of integers corresponding to the number of dimensions in the counter. This iterator will then return an N-dimensional counter.
`flatiter`