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B ��Fd%* � @ s\ d Z ddlmZmZmZ dgZddlmZ ddlm Z G dd� de �Z e dkrXe e � � dS ) z� Machine arithmetics - determine the parameters of the floating-point arithmetic system Author: Pearu Peterson, September 2003 � )�division�absolute_import�print_function�MachAr)�any)�errstatec @ s8 e Zd ZdZeeedd� dfdd�Zdd� Zd d � Zd S ) r a� Diagnosing machine parameters. 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)`` 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`. See Also -------- finfo : Machine limits for floating point types. iinfo : Machine limits for integer types. References ---------- .. 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Zbetahr, Ztempar" Zbetain�ir# r$ r% r& �k�z�tZnxres�yr' �mxZizr) r( r* r+ �jr. Ztenr1 r r r r t s\ $ $ zMachAr._do_initc C s d}|| j S )Na� Machine parameters for %(title)s --------------------------------------------------------------------- ibeta=%(ibeta)s it=%(it)s iexp=%(iexp)s ngrd=%(ngrd)s irnd=%(irnd)s machep=%(machep)s eps=%(_str_eps)s (beta**machep == epsilon) negep =%(negep)s epsneg=%(_str_epsneg)s (beta**epsneg) minexp=%(minexp)s xmin=%(_str_xmin)s (beta**minexp == tiny) maxexp=%(maxexp)s xmax=%(_str_xmax)s ((1-epsneg)*beta**maxexp == huge) --------------------------------------------------------------------- )�__dict__)r �fmtr r r �__str__G s zMachAr.__str__N) �__name__� __module__� __qualname__�__doc__�floatr/ r r rB r r r r r s O T�__main__N)rF � __future__r r r �__all__Znumpy.core.fromnumericr Znumpy.core.numericr �objectr rC �printr r r r �<module> s F