[Numpy-discussion] Numeric precision

Stephen Walton stephen.walton at csun.edu
Wed Oct 12 15:24:30 EDT 2005

Over on the scipy-dev mailing list, Travis Oliphant raised a question 
which is of interest to the folks over here as well.  To summarize very 
briefly, Travis wondered whether the rule of "safest conversion" might 
require that an integer to float computation conversion on a 64-bit 
platform would require promotion of, for example, sqrt(2) to a long 
double (128 bits).  I suggested that it would make the most sense for an 
M-bit integer to be converted to an N-bit real, where N>=M, on all 
platforms.  For example, sqrt(2) would become a 32-bit real if 2 was a 
32-bit integer on the plaform.

I am not sure if this is a change from current Numeric and numarray 
practice, but wanted to give a heads-up over here.  You can read the 
entire original thread beginning at


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