numpy.arange()

numpy.arange([start, ]stop, [step, ]dtype=None)

Return evenly spaced values within a given interval.

Values are generated within the half-open interval [start, stop) (in other words, the interval including start but excluding stop). For integer arguments the function is equivalent to the Python built-in range function, but returns an ndarray rather than a list.

When using a non-integer step, such as 0.1, the results will often not be consistent. It is better to use linspace for these cases.

Parameters:

Parameters:	start : number, optional Start of interval. The interval includes this value. The default start value is 0. stop : number End of interval. The interval does not include this value, except in some cases where `step` is not an integer and floating point round-off affects the length of `out`. step : number, optional Spacing between values. For any output `out`, this is the distance between two adjacent values, `out[i+1] - out[i]`. The default step size is 1. If `step` is specified, `start` must also be given. dtype : dtype The type of the output array. If `dtype` is not given, infer the data type from the other input arguments.
Returns:	arange : ndarray Array of evenly spaced values. For floating point arguments, the length of the result is `ceil((stop - start)/step)`. Because of floating point overflow, this rule may result in the last element of `out` being greater than `stop`.

start : number, optional

Start of interval. The interval includes this value. The default start value is 0.

stop : number

End of interval. The interval does not include this value, except in some cases where step is not an integer and floating point round-off affects the length of out.

step : number, optional

Spacing between values. For any output out, this is the distance between two adjacent values, out[i+1] - out[i]. The default step size is 1. If step is specified, start must also be given.

dtype : dtype

The type of the output array. If dtype is not given, infer the data type from the other input arguments.

Returns:

arange : ndarray

Array of evenly spaced values.

For floating point arguments, the length of the result is ceil((stop - start)/step). Because of floating point overflow, this rule may result in the last element of out being greater than stop.

Examples

>>> np.arange(3)
array([0, 1, 2])
>>> np.arange(3.0)
array([ 0.,  1.,  2.])
>>> np.arange(3,7)
array([3, 4, 5, 6])
>>> np.arange(3,7,2)
array([3, 5])

Links:

https://docs.scipy.org/doc/numpy-1.11.0/reference/generated/numpy.arange.html

doc_NumPy

2017-01-10 18:12:39

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