numpy.MachAr¶
-
class
numpy.
MachAr
(float_conv=<class 'float'>, int_conv=<class 'int'>, float_to_float=<class 'float'>, float_to_str=<function MachAr.<lambda>>, title='Python floating point number')[source]¶ Diagnosing machine parameters.
Parameters: - float_conv : function, optional
Function that converts an integer or integer array to a float or float array. Default is
float
.- int_conv : function, optional
Function that converts a float or float array to an integer or integer array. Default is
int
.- float_to_float : function, optional
Function that converts a float array to float. Default is
float
. Note that this does not seem to do anything useful in the current implementation.- float_to_str : function, optional
Function that converts a single float to a string. Default is
lambda v:'%24.16e' %v
.- title : str, optional
Title that is printed in the string representation of
MachAr
.
References
[1] Press, Teukolsky, Vetterling and Flannery, “Numerical Recipes in C++,” 2nd ed, Cambridge University Press, 2002, p. 31. Attributes: - ibeta : int
Radix in which numbers are represented.
- it : int
Number of base-ibeta digits in the floating point mantissa M.
- machep : int
Exponent of the smallest (most negative) power of ibeta that, added to 1.0, gives something different from 1.0
- eps : float
Floating-point number
beta**machep
(floating point precision)- negep : int
Exponent of the smallest power of ibeta that, subtracted from 1.0, gives something different from 1.0.
- epsneg : float
Floating-point number
beta**negep
.- iexp : int
Number of bits in the exponent (including its sign and bias).
- minexp : int
Smallest (most negative) power of ibeta consistent with there being no leading zeros in the mantissa.
- xmin : float
Floating point number
beta**minexp
(the smallest [in magnitude] usable floating value).- maxexp : int
Smallest (positive) power of ibeta that causes overflow.
- xmax : float
(1-epsneg) * beta**maxexp
(the largest [in magnitude] usable floating value).- irnd : int
In
range(6)
, information on what kind of rounding is done in addition, and on how underflow is handled.- ngrd : int
Number of ‘guard digits’ used when truncating the product of two mantissas to fit the representation.
- epsilon : float
Same as eps.
- tiny : float
Same as xmin.
- huge : float
Same as xmax.
- precision : float
- int(-log10(eps))
- resolution : float
- 10**(-precision)