diff options
Diffstat (limited to 'numpy/core/machar.py')
| -rw-r--r-- | numpy/core/machar.py | 52 |
1 files changed, 28 insertions, 24 deletions
diff --git a/numpy/core/machar.py b/numpy/core/machar.py index 9eb4430a6..6f2735d32 100644 --- a/numpy/core/machar.py +++ b/numpy/core/machar.py @@ -94,16 +94,19 @@ class MachAr(object): Cambridge University Press, 2002, p. 31. """ + 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_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 + + 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 + """ # We ignore all errors here because we are purposely triggering # underflow to detect the properties of the runninng arch. @@ -169,7 +172,7 @@ class MachAr(object): irnd = 1 tempa = a + beta temp = tempa + betah - if irnd==0 and any(temp-tempa != zero): + if irnd == 0 and any(temp-tempa != zero): irnd = 2 # Determine negep and epsneg @@ -188,7 +191,7 @@ class MachAr(object): # Prevent infinite loop on PPC with gcc 4.0: if negep < 0: raise RuntimeError("could not determine machine tolerance " - "for 'negep', locals() -> %s" % (locals())) + "for 'negep', locals() -> %s" % (locals())) else: raise RuntimeError(msg % (_, one.dtype)) negep = -negep @@ -211,7 +214,7 @@ class MachAr(object): # Determine ngrd ngrd = 0 temp = one + eps - if irnd==0 and any(temp*one - one != zero): + if irnd == 0 and any(temp*one - one != zero): ngrd = 1 # Determine iexp @@ -223,9 +226,9 @@ class MachAr(object): for _ in range(max_iterN): y = z z = y*y - a = z*one # Check here for underflow + a = z*one # Check here for underflow temp = z*t - if any(a+a == zero) or any(abs(z)>=y): + if any(a+a == zero) or any(abs(z) >= y): break temp1 = temp * betain if any(temp1*beta == z): @@ -251,7 +254,7 @@ class MachAr(object): y = y * betain a = y * one temp = y * t - if any(a+a != zero) and any(abs(y) < xmin): + if any((a + a) != zero) and any(abs(y) < xmin): k = k + 1 temp1 = temp * betain if any(temp1*beta == y) and any(temp != y): @@ -285,7 +288,7 @@ class MachAr(object): xmax = xmax / (xmin*beta*beta*beta) i = maxexp + minexp + 3 for j in range(i): - if ibeta==2: + if ibeta == 2: xmax = xmax + xmax else: xmax = xmax * beta @@ -322,16 +325,17 @@ class MachAr(object): self._str_resolution = float_to_str(resolution) def __str__(self): - return '''\ -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) ---------------------------------------------------------------------- -''' % self.__dict__ + fmt = ( + 'Machine parameters for %(title)s\n' + '---------------------------------------------------------------------\n' + 'ibeta=%(ibeta)s it=%(it)s iexp=%(iexp)s ngrd=%(ngrd)s irnd=%(irnd)s\n' + 'machep=%(machep)s eps=%(_str_eps)s (beta**machep == epsilon)\n' + 'negep =%(negep)s epsneg=%(_str_epsneg)s (beta**epsneg)\n' + 'minexp=%(minexp)s xmin=%(_str_xmin)s (beta**minexp == tiny)\n' + 'maxexp=%(maxexp)s xmax=%(_str_xmax)s ((1-epsneg)*beta**maxexp == huge)\n' + '---------------------------------------------------------------------\n' + ) + return fmt % self.__dict__ if __name__ == '__main__': |