class documentation

class MachAr:

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

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

[1]Press, Teukolsky, Vetterling and Flannery, "Numerical Recipes in C++," 2nd ed, Cambridge University Press, 2002, p. 31.
Method __init__ No summary
Method __str__ Undocumented
Method ​_do​_init Undocumented
Instance Variable ​_str​_eps Undocumented
Instance Variable ​_str​_epsneg Undocumented
Instance Variable ​_str​_resolution Undocumented
Instance Variable ​_str​_xmax Undocumented
Instance Variable ​_str​_xmin Undocumented
Instance Variable eps Undocumented
Instance Variable epsilon Undocumented
Instance Variable epsneg Undocumented
Instance Variable huge Undocumented
Instance Variable ibeta Undocumented
Instance Variable iexp Undocumented
Instance Variable irnd Undocumented
Instance Variable it Undocumented
Instance Variable machep Undocumented
Instance Variable maxexp Undocumented
Instance Variable minexp Undocumented
Instance Variable negep Undocumented
Instance Variable ngrd Undocumented
Instance Variable precision Undocumented
Instance Variable resolution Undocumented
Instance Variable smallest​_normal Undocumented
Instance Variable smallest​_subnormal Undocumented
Instance Variable tiny Undocumented
Instance Variable title Undocumented
Instance Variable xmax Undocumented
Instance Variable xmin Undocumented
def __init__(self, float_conv=float, int_conv=int, float_to_float=float, float_to_str=(lambda v: '%24.16e' % v), title='Python floating point number'):
float_conv - convert integer to float (array) int_conv - convert float (array) to integer float_to_float - convert float array to float float_to_str - convert array float to str title - description of used floating point numbers
def __str__(self):

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def _do_init(self, float_conv, int_conv, float_to_float, float_to_str, title):

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_str_eps =

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_str_epsneg =

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_str_resolution =

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_str_xmax =

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_str_xmin =

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eps =

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epsilon =

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epsneg =

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huge =

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ibeta =

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iexp =

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irnd =

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it =

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machep =

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maxexp =

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minexp =

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negep =

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ngrd =

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precision =

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resolution =

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smallest_normal =

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smallest_subnormal =

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tiny =

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title =

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xmax =

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xmin =

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