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
- 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] positive floating point number with full precision).- 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
An alias for smallest_normal, kept for backwards compatibility.
- hugefloat
Same as xmax.
- precisionfloat
- int(-log10(eps))- resolutionfloat
- 10**(-precision)- smallest_normalfloat
The smallest positive floating point number with 1 as leading bit in the mantissa following IEEE-754. Same as xmin.
- smallest_subnormalfloat
The smallest positive floating point number with 0 as leading bit in the mantissa following IEEE-754.