mars.tensor.special.erf

mars.tensor.special.erf(x, out=None, where=None, **kwargs)[源代码]

Returns the error function of complex argument.

It is defined as 2/sqrt(pi)*integral(exp(-t**2), t=0..z).

参数

x (Tensor) – Input tensor.

返回

res – The values of the error function at the given points x.

返回类型

Tensor

参见

erfc, erfinv, erfcinv, wofz, erfcx, erfi

提示

The cumulative of the unit normal distribution is given by Phi(z) = 1/2[1 + erf(z/sqrt(2))].

引用

1

https://en.wikipedia.org/wiki/Error_function

2

Milton Abramowitz and Irene A. Stegun, eds. Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables. New York: Dover, 1972. http://www.math.sfu.ca/~cbm/aands/page_297.htm

3

Steven G. Johnson, Faddeeva W function implementation. http://ab-initio.mit.edu/Faddeeva

实际案例

>>> import mars.tensor as mt
>>> from mars.tensor import special
>>> import matplotlib.pyplot as plt
>>> x = mt.linspace(-3, 3)
>>> plt.plot(x, special.erf(x))
>>> plt.xlabel('$x$')
>>> plt.ylabel('$erf(x)$')
>>> plt.show()