select part of array using two conditions

Nils Wagner nwagner at iam.uni-stuttgart.de
Wed Oct 11 04:29:26 CDT 2006


Mark Bakker wrote:
> Hello -
>
> I want to select part of an array using two conditions.
> I know how to do it with one condition (and it works great), but when
> I use two conditions I get an error message?
> This is probably easy, but I cannot figure it out.
> Thanks for any help, Mark
>
> >>> a = arange(10)
> >>> a
> array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
> >>> a[ a>2 ]
> array([3, 4, 5, 6, 7, 8, 9])
> >>> a[ a>2 and a<8 ]
> Traceback (most recent call last):
>   File "<pyshell#52>", line 1, in ?
>     a[ a>2 and a<8 ]
> ValueError: The truth value of an array with more than one element is
> ambiguous. Use a.any() or a.all()
>
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>   
a[ (a>2) & (a<8) ]

Nils
 

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Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642




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