Constants NumPy includes several constants:   numpy.Inf
 
IEEE 754 floating point representation of (positive) infinity. Use inf because Inf, Infinity, PINF and infty are aliases for inf. For more details, see inf. See Also inf 
   numpy.Infinity
 
IEEE 754 floating point representation of (positive) infinity. Use inf because Inf, Infinity, PINF and infty are aliases for inf. For more details, see inf. See Also inf 
   numpy.NAN
 
IEEE 754 floating point representation of Not a Number (NaN). NaN and NAN are equivalent definitions of nan. Please use nan instead of NAN. See Also nan 
   numpy.NINF
 
IEEE 754 floating point representation of negative infinity. Returns  yfloat


A floating point representation of negative infinity.   See Also isinf : Shows which elements are positive or negative infinity isposinf : Shows which elements are positive infinity isneginf : Shows which elements are negative infinity isnan : Shows which elements are Not a Number isfinite : Shows which elements are finite (not one of Not a Number, positive infinity and negative infinity) Notes NumPy uses the IEEE Standard for Binary Floating-Point for Arithmetic (IEEE 754). This means that Not a Number is not equivalent to infinity. Also that positive infinity is not equivalent to negative infinity. But infinity is equivalent to positive infinity. Examples >>> np.NINF
-inf
>>> np.log(0)
-inf
 
   numpy.NZERO
 
IEEE 754 floating point representation of negative zero. Returns  yfloat


A floating point representation of negative zero.   See Also PZERO : Defines positive zero. isinf : Shows which elements are positive or negative infinity. isposinf : Shows which elements are positive infinity. isneginf : Shows which elements are negative infinity. isnan : Shows which elements are Not a Number.  isfiniteShows which elements are finite - not one of


Not a Number, positive infinity and negative infinity.   Notes NumPy uses the IEEE Standard for Binary Floating-Point for Arithmetic (IEEE 754). Negative zero is considered to be a finite number. Examples >>> np.NZERO
-0.0
>>> np.PZERO
0.0
 >>> np.isfinite([np.NZERO])
array([ True])
>>> np.isnan([np.NZERO])
array([False])
>>> np.isinf([np.NZERO])
array([False])
 
   numpy.NaN
 
IEEE 754 floating point representation of Not a Number (NaN). NaN and NAN are equivalent definitions of nan. Please use nan instead of NaN. See Also nan 
   numpy.PINF
 
IEEE 754 floating point representation of (positive) infinity. Use inf because Inf, Infinity, PINF and infty are aliases for inf. For more details, see inf. See Also inf 
   numpy.PZERO
 
IEEE 754 floating point representation of positive zero. Returns  yfloat


A floating point representation of positive zero.   See Also NZERO : Defines negative zero. isinf : Shows which elements are positive or negative infinity. isposinf : Shows which elements are positive infinity. isneginf : Shows which elements are negative infinity. isnan : Shows which elements are Not a Number.  isfiniteShows which elements are finite - not one of


Not a Number, positive infinity and negative infinity.   Notes NumPy uses the IEEE Standard for Binary Floating-Point for Arithmetic (IEEE 754). Positive zero is considered to be a finite number. Examples >>> np.PZERO
0.0
>>> np.NZERO
-0.0
 >>> np.isfinite([np.PZERO])
array([ True])
>>> np.isnan([np.PZERO])
array([False])
>>> np.isinf([np.PZERO])
array([False])
 
   numpy.e
 
Euler’s constant, base of natural logarithms, Napier’s constant. e = 2.71828182845904523536028747135266249775724709369995... See Also exp : Exponential function log : Natural logarithm References https://en.wikipedia.org/wiki/E_%28mathematical_constant%29 
   numpy.euler_gamma
 
γ = 0.5772156649015328606065120900824024310421... References https://en.wikipedia.org/wiki/Euler-Mascheroni_constant 
   numpy.inf
 
IEEE 754 floating point representation of (positive) infinity. Returns  yfloat


A floating point representation of positive infinity.   See Also isinf : Shows which elements are positive or negative infinity isposinf : Shows which elements are positive infinity isneginf : Shows which elements are negative infinity isnan : Shows which elements are Not a Number isfinite : Shows which elements are finite (not one of Not a Number, positive infinity and negative infinity) Notes NumPy uses the IEEE Standard for Binary Floating-Point for Arithmetic (IEEE 754). This means that Not a Number is not equivalent to infinity. Also that positive infinity is not equivalent to negative infinity. But infinity is equivalent to positive infinity. Inf, Infinity, PINF and infty are aliases for inf. Examples >>> np.inf
inf
>>> np.array([1]) / 0.
array([ Inf])
 
   numpy.infty
 
IEEE 754 floating point representation of (positive) infinity. Use inf because Inf, Infinity, PINF and infty are aliases for inf. For more details, see inf. See Also inf 
   numpy.nan
 
IEEE 754 floating point representation of Not a Number (NaN). Returns y : A floating point representation of Not a Number. See Also isnan : Shows which elements are Not a Number. isfinite : Shows which elements are finite (not one of Not a Number, positive infinity and negative infinity) Notes NumPy uses the IEEE Standard for Binary Floating-Point for Arithmetic (IEEE 754). This means that Not a Number is not equivalent to infinity. NaN and NAN are aliases of nan. Examples >>> np.nan
nan
>>> np.log(-1)
nan
>>> np.log([-1, 1, 2])
array([        NaN,  0.        ,  0.69314718])
 
   numpy.newaxis
 
A convenient alias for None, useful for indexing arrays. Examples >>> newaxis is None
True
>>> x = np.arange(3)
>>> x
array([0, 1, 2])
>>> x[:, newaxis]
array([[0],
[1],
[2]])
>>> x[:, newaxis, newaxis]
array([[[0]],
[[1]],
[[2]]])
>>> x[:, newaxis] * x
array([[0, 0, 0],
[0, 1, 2],
[0, 2, 4]])
 Outer product, same as outer(x, y): >>> y = np.arange(3, 6)
>>> x[:, newaxis] * y
array([[ 0,  0,  0],
[ 3,  4,  5],
[ 6,  8, 10]])
 x[newaxis, :] is equivalent to x[newaxis] and x[None]: >>> x[newaxis, :].shape
(1, 3)
>>> x[newaxis].shape
(1, 3)
>>> x[None].shape
(1, 3)
>>> x[:, newaxis].shape
(3, 1)
 
   numpy.pi
 
pi = 3.1415926535897932384626433... References https://en.wikipedia.org/wiki/Pi