Mailing-List: contact user-help@uima.apache.org; run by ezmlm
Precedence: bulk
Reply-To: user@uima.apache.org
Received-SPF: pass (athena.apache.org: domain of msa@schor.com designates
 69.41.245.8 as permitted sender)
Message-ID: <4BDEED76.70107@schor.com>
Date: Mon, 03 May 2010 11:36:22 -0400
From: Marshall Schor <msa@schor.com>
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US;
 rv:1.9.1.9) Gecko/20100317 Thunderbird/3.0.4
MIME-Version: 1.0
To: user@uima.apache.org
Subject: Re: determining whether a feature has been set
References: <loom.20100503T150719-287@post.gmane.org>
 <4BDED77E.4060405@gmx.de>
In-Reply-To: <4BDED77E.4060405@gmx.de>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

You could pick a value which won't occur otherwise.

For instance, Float has a special value Float.NaN, which is not a
number.  (If you use this, remember that the equals test doesn't work on
this.)
Integers don't have any such value, but some codes use
Integer.MIN_VALUE, if it won't occur otherwise.

Finally, you could define another feature in your FeatureStructure, of
type boolean, and set that to false initially, and true when you set the
feature of interest.

-Marshall

On 5/3/2010 10:02 AM, Thilo Goetz wrote:
> On 5/3/2010 15:15, Klaus Rothenhäusler wrote:
>   
>> Hi,
>> is there any way to determine whether a feature of a primitive
>> numerical type has been set in a particular feature structure? The
>> methods like getIntValue(feat), getFloatValue(feat), etc. all return a
>> zero value if the feature hasn't been set. But zero is of course a
>> perfectly plausible value in many domains.
>>
>> Thanks
>> --Klaus Rothenhäusler
>>     
> There is no way to check this.  We do not wrap primitive
> values internally, and so do not attach any metadata like,
> has it been set or not.  It's like a Java primitive variable
> in that sense.
>
> --Thilo
>
>
>