[mapserver-users] RE: CLASS EXPRESSION regex help?

[Lime, Steve D (DNR)]

>From the class.html file under the EXPRESSION property:

"Four types of expressions are now supported to define class membership. String comparisons, regular expressions, simple logical expressions, and string functions. If no expression is given, then all features are said to belong to this class."

Perhaps not the best explanation but the last sentence is pretty clear.

Steve

-----Original Message-----
From: mapserver-users-bounces at lists.osgeo.org [mailto:mapserver-users-bounces at lists.osgeo.org] On Behalf Of Jeff McKenna
Sent: Friday, July 23, 2010 11:43 AM
To: mapserver-users at lists.osgeo.org
Subject: Re: [mapserver-users] RE: CLASS EXPRESSION regex help?

Are all of these tricks discussed here documented somewhere?

-jeff



-- 
Jeff McKenna
MapServer Consulting and Training Services
http://www.gatewaygeomatics.com/




Lime, Steve D (DNR) wrote:
> If all of your classes have expressions then there is no default and some features will not be drawn. You kinda get the best of both worlds with this approach...
> 
> Steve
> 
> -----Original Message-----
> From: mapserver-users-bounces at lists.osgeo.org [mailto:mapserver-users-bounces at lists.osgeo.org] On Behalf Of Johan Forsman
> Sent: Friday, July 23, 2010 10:39 AM
> To: mapserver-users at lists.osgeo.org
> Subject: [mapserver-users] RE: CLASS EXPRESSION regex help?
> 
> Thanks Steve, that appears to work!
> 
> I did not realize MapServer would on its own accord exclude the already CLASSified records from the second CLASS unless I explicitly instructed it what to exclude. I presumed it would just draw them again together with the rest. Nice!
> 
> Thanks!
> 
> Now back to monitoring the brewing storm in the Gulf.
> 
>> -----Original Message-----
>> From: Lime, Steve D (DNR) [mailto:Steve.Lime at state.mn.us]
>> Sent: Friday, July 23, 2010 10:01 AM
>> To: Johan Forsman; mapserver-users at lists.osgeo.org
>> Subject: RE: CLASS EXPRESSION regex help?
>>
>> Hi Johan: Are you looking for just two classes, one for records that start
>> with "LADE" and another for everything else? If so you can just omit the
>> expression from the second class and it will function as a default class
>> so everything that doesn't match the first will be assigned the second.
>> It's faster to execute than trying to expressly define a second regex.
>> Doesn't solve the regex error but then again you may not need to.
>>
>> Steve
>>
>> -----Original Message-----
>> From: mapserver-users-bounces at lists.osgeo.org [mailto:mapserver-users-
>> bounces at lists.osgeo.org] On Behalf Of Johan Forsman
>> Sent: Friday, July 23, 2010 9:20 AM
>> To: mapserver-users at lists.osgeo.org
>> Subject: [mapserver-users] CLASS EXPRESSION regex help?
>>
>> All:
>>
>> Regex neophyte, using MS 5.4.2 in FGS on Ubuntu Server 9.10, I wish to
>> render two classes based on content in a PostGIS field.
>>
>> For the first CLASS I want all records that start with "LADE", and using
>>
>> NAME "LADE"
>> EXPRESSION /^LADE.*/
>>
>> appears to return the expected records.
>>
>> However, for the second CLASS I want all records that DO NOT start with
>> "LADE", but using
>>
>> NAME "Other"
>> EXPRESSION /^(?!LADE).*/
>>
>> does not return any records and the log contains
>>
>> msEvalExpression() error: Regular expression error. Invalid regular
>> expression.
>>
>> Examples out in the ether all indicate that this "negative lookahead" is
>> supposed to do exactly what I want.
>>
>> What am I doing wrong in this instance?
>>
>> Thanks!
>> /Johan.
>>
>> ----------------------
>> Johan Forsman
>> Geologist
>> Safe Drinking Water Program
>> Louisiana Department of Health and Hospitals
>> Office of Public Health
>> Telephone: 225.342.7309
>> Telefax: 225.342.7303
>>
>>
_______________________________________________
mapserver-users mailing list
mapserver-users at lists.osgeo.org
http://lists.osgeo.org/mailman/listinfo/mapserver-users