Another question about shapefiles

[Stephen Woodbridge]

So if I understand correctly what you really want to do, is to geocode you
database records with a lat/lon based on there zipcode. Then you want to
present the database data as a layer of points based on this lat/lon
value.

If so then you should write a script to add lat, lon columns to your
database and then for every record in the database populate the lat, lon
based on the zipcode. If you load the zipcode, lat, lon as a new table you
can dothis on the fly with a join.

Regardless if I understand what you are asking for, youdon't need to
create a shape layer from the zipcode data and even if you did, you would
then be able to display the zipcodes as labels at the zipcode points but
you would have no way to display the mysql data at the respective points.

Hope this makes sense.
  -Steve

Joseph Norris said:
> Steve,
>
> Thanks for this information.  I understand this.  However here is my
> situation.  I have a shapefile of California.  It has its dbf file.
>
> This is a sample:
>
> 0.859846443800379:5.7057500729921:50:49:06:053:Monterey:06:County
> 1.25622233242418:5.28286812594892:51:50:06:107:Tulare:06:County
>
>
> I have another text file of zip codes with lat/long codes.
>
> "01","35004","AL","ACMAR",86.51557,33.584132,6055,0.001499
> "01","35005","AL","ADAMSVILLE",86.959727,33.588437,10616,0.002627
> "01","35006","AL","ADGER",87.167455,33.434277,3205,0.000793
> "01","35007","AL","KEYSTONE",86.812861,33.236868,14218,0.003519
> "01","35010","AL","NEW SITE",85.951086,32.941445,19942,0.004935
> "01","35014","AL","ALPINE",86.208934,33.331165,3062,0.000758
>
>
> I have the whole US - so I have California.
>
> What I am trying to accomplish is to layer the zip code data on top of
> California an by that read a Mysql user table and by zip code place a
> symbol
> where these users are located.
>
> I am doing all of this from a ESRI background that would have made this an
> easier via the GUI but not as much fun and definitely not Open Source.
>
>
>   BTW - I am doing all of this as proof of concept so that my company will
> get into GIS as an extension of  one of the best Open Source  content
> management systems I have ever worked on - OK - enough of that - but it is
> a
> really well designed product.
>
> #Joseph Norris (Perl - what else is there?/Linux/CGI/Mysql) print @c=map
> chr
> $_+100,(6,17,15,16,-68,-3,10,11,16,4,1,14,-68,12,1,14,8,-68,4,-3,-1,7,1,14,-
> 68,-26,11,15,1,12,4,-68,-22,11,14,14,5,15,-90);
>
> -----Original Message-----
> From: Stephen Woodbridge [mailto:woodbri at swoodbridge.com]
> Sent: Monday, November 15, 2004 4:12 AM
> To: Joseph Norris
> Cc: MAPSERVER-USERS at LISTS.UMN.EDU
> Subject: Re: [UMN_MAPSERVER-USERS] Another question about shapefiles
>
> Joseph,
>
> In the C interface I think you can open a file in mode "rb+" which will
> allow you to read/write, BUT in general practice I would open the file
> for read, copy it record by record, and then add any new data to the
> file. Otherwise you run the risk of damaging your original file.
> Typically if you need to do this via a multi-user interface, like a web
> form you need to edit a database and not a shapefile as this library has
> not locking and it WILL get trashed.
>
> -Steve
>
> Joseph Norris wrote:
>
>> Stephen,
>>
>> These are really great - I was able to build my shape file from zip file
>> very easily.  Now the question is - and I have experimented.
>>
>> I see in the Shapelib docs I see that I can open a shapefile that
>> already
>> exists.  Can I then read another file of points and the put these points
> on
>> the original shape?
>>
>> No matter what I do I am getting errors back.   I can only find examples
> of
>> code in the pod for the module.
>>
>> Thanks for all your help.
>>
>> #Joseph Norris (Perl - what else is there?/Linux/CGI/Mysql) print @c=map
> chr
>>
> $_+100,(6,17,15,16,-68,-3,10,11,16,4,1,14,-68,12,1,14,8,-68,4,-3,-1,7,1,14,-
>> 68,-26,11,15,1,12,4,-68,-22,11,14,14,5,15,-90);
>>
>> -----Original Message-----
>> From: UMN MapServer Users List [mailto:MAPSERVER-USERS at lists.umn.edu]On
>> Behalf Of Stephen Woodbridge
>> Sent: Sunday, November 14, 2004 6:14 PM
>> To: MAPSERVER-USERS at lists.umn.edu
>> Subject: Re: [UMN_MAPSERVER-USERS] Another question about shapefiles
>>
>> Joseph,
>>
>> Check out perl modules:
>>
>> Geo::ShapeFile
>> Geo::Shapelib
>> XBase
>>
>> These are handy modules for working with shapefiles and the DBF
>> attributes file. I write scripts all the time for creating, reading and
>> manipulating shapefiles. When I need more performance I usually use the
>> shapelib library and C code.
>>
>> -Steve
>>
>> Joseph Norris wrote:
>>
>>>I have a US zip file containing zip codes and associated lat/long
>>>information.  Can I convert this to points on a shapefile?
>>>
>>>#Joseph Norris (Perl - what else is there?/Linux/CGI/Mysql) print @c=map
>>
>> chr
>>
>>
> $_+100,(6,17,15,16,-68,-3,10,11,16,4,1,14,-68,12,1,14,8,-68,4,-3,-1,7,1,14,-
>>
>>>68,-26,11,15,1,12,4,-68,-22,11,14,14,5,15,-90);
>>>
>>
>>
>
>