help numpy.linspace
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Help on function linspace in module numpy: linspace(start, stop, num=50, endpoint=True, retstep=False, dtype=None, axis=0) Return evenly spaced numbers over a specified interval. Returns
Parameters start : array_like The starting value of the sequence. stop : array_like The end value of the sequence, unless num : int, optional Number of samples to generate. Default is 50. Must be non-negative. endpoint : bool, optional If True, retstep : bool, optional If True, return ( dtype : dtype, optional The type of the output array. If
versionadded::1.9.0 axis : int, optional The axis in the result to store the samples. Relevant only if start or stop are array-like. By default (0), the samples will be along a new axis inserted at the beginning. Use -1 to get an axis at the end.
versionadded::1.16.0 Returns ------- samples : ndarray There are
Examples
Graphical illustration:
num
evenly spaced samples, calculated over the interval [ start
, stop
]. The endpoint of the interval can optionally be excluded. versionchanged::1.16.0 Non-scalar start
and stop
are now supported. Parameters
endpoint
is set to False. In that case, the sequence consists of all but the last of num + 1
evenly spaced samples, so that stop
is excluded. Note that the step size changes when endpoint
is False. stop
is the last sample. Otherwise, it is not included. Default is True. samples
, step
), where step
is the spacing between samples. dtype
is not given, infer the data type from the other input arguments. versionadded::1.9.0
versionadded::1.16.0 Returns ------- samples : ndarray There are
num
equally spaced samples in the closed interval [start, stop]
or the half-open interval [start, stop)
(depending on whether endpoint
is True or False). step : float, optional Only returned if retstep
is True Size of spacing between samples. See Also -------- arange : Similar to linspace
, but uses a step size (instead of the number of samples). geomspace : Similar to linspace
, but with numbers spaced evenly on a log scale (a geometric progression). logspace : Similar to geomspace
, but with the end points specified as logarithms. Examples
>>> import numpy as np
>>> np.linspace(2.0, 3.0, num=5)
array([2. , 2.25, 2.5 , 2.75, 3. ])
>>> np.linspace(2.0, 3.0, num=5, endpoint=False)
array([2. , 2.2, 2.4, 2.6, 2.8])
>>> np.linspace(2.0, 3.0, num=5, retstep=True)
(array([2. , 2.25, 2.5 , 2.75, 3. ]), 0.25)
Graphical illustration:
import numpy as np
import matplotlib.pyplot as plt
N = 8
y = np.zeros(N)
x1 = np.linspace(0, 10, N, endpoint=True)
x2 = np.linspace(0, 10, N, endpoint=False)
plt.plot(x1, y, 'o')
plt.plot(x2, y + 0.5, 'o')
plt.ylim([-0.5, 1])
plt.show()