[Numpy-discussion] numpy.fromstring() : error handling ?
Christopher Barker
Chris.Barker at noaa.gov
Sat Aug 9 02:18:29 EDT 2008
oc-spam66 wrote:
> Is it really how it should be ?
>
> I thought this method should be restrictive in what it accepts (because
> the goal is to fill an array with precise dimensions).
if you know how big an array you want, then you should use the "count"
keyword:
np.fromstring("45.6 76.4", dtype=np.float, sep = ' ', count = 1)
> When floating
> point numbers are mixed with something else, it should be parsed with a
> regexp.
Or any number of other ways. Yes, fromstring (and from file) is for only
the simplest of needs, very efficiently pulling a bunch of numbers from
text.
In any case, your example shows a bug, plain and simple. Parsing
"kjhsdf" should not produce the number zero, period. I suppose what it
should do it up for debate, it could either raise an exception or return
an empty array. By the way, I've found another bug:
>> np.fromstring("23 ", dtype=np.float, sep=" ", count=2)
array([ 3.400000000e+01, 1.09284155e-305])
That really should raise an exception rather than returning garbage!
Oh well, it looks like there is some work to be done.
-Chris
--
Christopher Barker, Ph.D.
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