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_convfunction, optional
Function that converts an integer or integer array to a float or float array. Default is
float
.- int_convfunction, optional
Function that converts a float or float array to an integer or integer array. Default is
int
.- float_to_floatfunction, 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_strfunction, optional
Function that converts a single float to a string. Default is
lambda v:'%24.16e' %v
.- titlestr, optional
Title that is printed in the string representation of
MachAr
.
References
- Re860718f5533-1
Press, Teukolsky, Vetterling and Flannery, “Numerical Recipes in C++,” 2nd ed, Cambridge University Press, 2002, p. 31.
- Attributes
- ibetaint
Radix in which numbers are represented.
- itint
Number of base-ibeta digits in the floating point mantissa M.
- machepint
Exponent of the smallest (most negative) power of ibeta that, added to 1.0, gives something different from 1.0
- epsfloat
Floating-point number
beta**machep
(floating point precision)- negepint
Exponent of the smallest power of ibeta that, subtracted from 1.0, gives something different from 1.0.
- epsnegfloat
Floating-point number
beta**negep
.- iexpint
Number of bits in the exponent (including its sign and bias).
- minexpint
Smallest (most negative) power of ibeta consistent with there being no leading zeros in the mantissa.
- xminfloat
Floating point number
beta**minexp
(the smallest [in magnitude] usable floating value).- maxexpint
Smallest (positive) power of ibeta that causes overflow.
- xmaxfloat
(1-epsneg) * beta**maxexp
(the largest [in magnitude] usable floating value).- irndint
In
range(6)
, information on what kind of rounding is done in addition, and on how underflow is handled.- ngrdint
Number of ‘guard digits’ used when truncating the product of two mantissas to fit the representation.
- epsilonfloat
Same as eps.
- tinyfloat
Same as xmin.
- hugefloat
Same as xmax.
- precisionfloat
- int(-log10(eps))
- resolutionfloat
- 10**(-precision)