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GIS/GPS Programming

The Global Positioning System (GPS) is a space-based global navigation satellite system (GNSS) that provides reliable location and time information in all weather and at all times and anywhere on or near the Earth when and where there is an unobstructed line of sight to four or more GPS satellites. A geographic information system (GIS) or geospatial information system is any system that captures, stores, analyzes, manages, and presents data that are linked to location(s). In the simplest terms, GIS is the merging of cartography, statistical analysis, and database technology.

We have a license for Google Maps API.  I'm a novice at creating Maps.  We need a map of all philadelphia police districts, and then we need to add in our own map points (longitude/latitude).   I found this link:


it's exactly what we need, except for our own map points.  Can I somehow make use of this page and/or extract from the source the shapes that are the police districts, and then use this with the Google Maps API?
Given a set of points (latitude/longitude) that make a location polygon, how would you determine the straight line distance between this polygon and  separate point (lat/long)?  In essence how do we calculate the proximity to the polygon?
I'm trying to use a calculation in my query to see if any other entries exist within a certain radius of my original latitude and longitude.  I'm trying to use the below and hardcoded in the 1500 miles for testing, but I'm not getting results, when I should be receiving ~1k.

Do I have a typo?

select county_name, cz.latitude as latitude, cz.longitude as longitude, sum(population) as population, 
( 3959 * acos( cos( radians('1500') ) * cos( radians( cz.latitude ) ) * cos( radians( cz.longitude ) - radians('1500') ) + sin( radians('1500') ) * sin( radians( cz.latitude ) ) ) ) AS distance
            from county_zip cz
            inner join county_state_master csm on cz.county = csm.county_name
            inner join rttc_gender rg on csm.id = rg.county_state_id
            where gender = 'M'
            and cz.zip_code = "64068"
			having distance < 1500
            order by population desc limit 200

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Historically, iPads have not had real GPS. The GPS they have goes through a cell phone network, called Assisted GPS. Now I hear that iPads are coming with real GPS. How do I know if a particular iPad has real GPS?

We've ordered  Part number MH312LL/A with Verizon iPad non-SIM Card (HH702LL/A)
I am trying to find the closest point on a line.

Based on some articles I used the following:


But the result returns a null.  Any ideas?  I have attached the sql that I am using on SQL 2008 R2
Ideally, I would like to be able to have our office staff program our GPS "route for the day".  Ideally, they would give us a printed schedule, complete with phone numbers and specific suggestions, and the route would already be in the GPS when we hit the road.  Is it possible to have someone program the GPS either over a cell phone signal, or via a wireless network when the vehicle is in range?

Assistance is greatly appreciated.
I'm looking for a way to track our fleet in Google map.
Our fleet drivers all have ipad. We get their coordinates through a small customized ipad program installed on it, then coordinates are sent and saved to our central location's SQL database aslongitude and latititude coordinates. There are about 100 vehicles.

How to show them all in one google map? I briefly searched in Google, it seems like they charge monthly to track  a fleet. Is this the only solution?

I have GPS longitudes and latitudes saved in SQL server, it has format of dddd.dddd and Hemisphere value.
How do I convert this in SQL on fly so that Google map accepts it.
For example, one has;
LastGPS_Latitude      LastGPS_LatHemisphere      LastGPS_Longitude
4045.2576      N      7352.8029

This coordinate is supposed to show somewhere in New York city or close.
I have a:

- Samsung Tab4 (KitKat)
- Verizon Wireless MiFi

And need excellent mapping, for driving. I will mount the Samsung Tab4 (KitKat) on the dashboard so I can look at it head's up. What's a good way to do this since it's larger than a cell phone?

Also, can I have the device show its location? I have not done this with my Android, only a cellphone up until now...

When the user opens the map, I want to show the entire country.  After they select an area and hit the "submit" button, I want the map to center on the new searched location and increase the zoom 10 10.  I am passing the searchmarkerlat and searchmarkerlng,  but cant get the map to change the center.
I've created a bunch of Placemarks and have them in a kml file.
Is there a way to get this into the GPS of a car?
Disclaimer - I'm completely unfamiliar with HTML.  I have an existing XSL template that lists all the fields and their values and I want to only select a specific field (rather than all of the fields) and refer to it multiple times so that I can provide hyperlinks to documents that have that field's value in it's file path like the following:
<xsl:attribute name="href">Q:\A_DPW\Images\WaterTieCards\<xsl:value-of select="FieldValue"/>.pdf

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...and then
<xsl:attribute name="href">Q:\A_DPW\Images\SewerTieCards\<xsl:value-of select="FieldValue"/>.pdf

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Here's the entire XSL template:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:fo="http://www.w3.org/1999/XSL/Format">
      <xsl:template match="/">
					<meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
                        <xsl:variable name="nameCol" select="FieldsDoc/Fields/Field/FieldName"/>
                              <table border="1" width="300" cellpadding="5" cellspacing="0">
                                    <tr bgcolor="#9cbce2">
                                          <xsl:if test="string-length($nameCol) != 0">
                                                <th width="50%" align="left">Field Name</th>
                                          <th width="50%" 

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I have a bunch of PDF drawings that are listing in a BRIDGEPHOTO Table in SQL Server 2012 , Problem is some of the pdf names include the "&" symbol. This is a reserved word in ESRI and the attachments are not working.

I would just like to Delete that from the name all together.
So Plan&Profile becomes PlanProfile or Plan_Profile
I can replace with and "_" as well. Either way is good with me.

SELECT REPLACE(AliasName,'&', '')
Where AliasName Like '&'

I'm not sure if this is right and was hoping to double check, Plus get some feedback on the best way to do this.
I have to lat/lon Points. I want to draw a line segment between the 2, but I don't see functionality in Google Earth to do this. LineString is not it. Surely I am missing something.
I have created this kml manually and I can't get it to display correctly. The point will display correctly, but not the polygon.What am I doing wrong?

<?xml version="1.0" encoding="UTF-8"?> 
<kml xmlns="http://earth.google.com/kml/2.0"> 


           -107.0972543, 32.67182529, 0.0

                      -106.6821846, 32.69174411,    0.0
                      -107.9140075, 31.78357488,    0.0
                      -106.6821846, 32.69174411,    0.0



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Hello Experts,

I am a new ArcMap and have a formatting issue.  I am using ArcMap 10 and Oracle 10g.  Here is my issue:

My table "Hub_Tickets" in oracle has a field called "Impact_Score" that is a number format. When I add this table to a ArcMap session, I go to "Open" and find the field and it shows that it's a "Long" character.  Here is the issue, when I review the records it shows 0, and not the real values "1 through 5,000,000".  This isn't the only field it does this to. It only changes number format field values.

I tried changing the format in Oracle to text and it works, the numbers are displayed but that are text so I can't use the symbology to make ranges for color changes.

I also tried in the Catalog -->table properties --> Fields tab, and change the data type.  I get error of Unable to alter the field's type  ORA-00942: Table or view does not exist.

Any idea what I should do?

**UPDATE**  I did have come across another table that has values showing that are long types.  The difference I see is that the "precision" has a number 10. Where as my field doesn't have that precision listed.  Any ideas?

Update 2

I had to format the field like this.  Any reason why?  I have many other fields and it seems that it would be a lot of time to do so.  Using views.. too
The feature of being able to pull in a kml file from a ?q= querystring on to a googlemap is being decpracted in favour of Google's newer My Map system:

Viewing KML data in Google Maps

You may have received a notification in product saying "A Google Maps feature used on this page is changing soon. Custom map content will need to be migrated."

After February 2015, you will no longer able to view custom KML content in the classic version of Google Maps. KML is the file format Google Earth uses for the exchange of geographic information.


I currently generate a kml file from a database depending on various parameters and display if using a URL: https://maps.google.com/maps?hl=en&q=http://www.smartinsight.co.uk/loyalty/kml/MemberCount-29.kml&ie=UTF8&t=m&source=embed&output=classic&dg=feature

From February I will not be able to do this!

Can anyone show me a way of using a similar method with Google My Map or any other way to continue to include a kml file via a querystring in their new system.

We have noticed In certain apps that uses GPS, that even though there is no internet access, the GPS seems to work.  We come to this conclusion because the pointer keeps moving.  If this is the case, how does the cell gets it's data?
Does anyone know of an Android App that will disable/hide/obfuscate your GPS location when the phone is close to important locations (home, work, etc.).
I am busy learning Postgres with the goal of migrating our current MySQL database to a Postgres/PostGIS spatial database.

We have a table containing (multi)polygons and do a large number of queries that need to find the properties within a given radius of a specific property. In MySQL I have Lat and Lon columns (in radians, of the property centroids) and use the great circle formula to do this.

I was reading about ways of improving performance in Postgres and came across a section titled "Cluster tables on specific indexes".

My question is: Does this work with spatial (gist) indexes to cluster the table by proximity of geometries?
This is a sample of Alaska someone found on the web for me, but who said it had only 40 states. Can someone please direct me to all 50 states?

Coming from the same source is best.

<state name ="Alaska" colour="#ff0000" >
  <point lat="70.0187" lng="-141.0205"/>
  <point lat="70.1292" lng="-141.7291"/>
  <point lat="70.4515" lng="-144.8163"/>
  <point lat="70.7471" lng="-148.4583"/>
  <point lat="70.7923" lng="-151.1609"/>
  <point lat="71.1470" lng="-152.6221"/>
  <point lat="71.1185" lng="-153.9954"/>
  <point lat="71.4307" lng="-154.8853"/>
  <point lat="71.5232" lng="-156.7529"/>
  <point lat="71.2796" lng="-157.9449"/>
  <point lat="71.2249" lng="-159.6313"/>
  <point lat="70.6363" lng="-161.8671"/>
  <point lat="70.0843" lng="-163.5809"/>
  <point lat="69.3028" lng="-165.2399"/>
  <point lat="69.1782" lng="-166.8768"/>
  <point lat="68.3344" lng="-168.0414"/>
  <point lat="67.6844" lng="-165.9155"/>
  <point lat="67.2933" lng="-164.6082"/>
  <point lat="66.7789" lng="-164.0149"/>
  <point lat="66.5810" lng="-165.7507"/>
  <point lat="66.2867" lng="-167.5745"/>
  <point lat="66.0269" lng="-168.9862"/>
  <point lat="65.4970" lng="-168.9478"/>
  <point lat="65.0420" lng="-167.4756"/>
  <point lat="64.3922" lng="-167.0142"/>
  <point lat="64.0554" lng="-165.7343"/>
  <point lat="64.0193" lng="-163.2294"/>
  <point lat="63.9615" lng="-162.1143"/>
  <point lat="63.6877" lng="-163.6029"/>
  <point lat="63.4530" lng="-165.3717"/>
I had an iPhone 4S and it was perfectly integrating with my Tom Tom GO 50 for live traffic data. Then I got an iPhone 6 and can not find a free app of iTunes to download.

What version of the app on iTunes will use Bluetooth to provide live traffic data to my Tom Tom GO 50?

I have a little confuse about compare  google map API and GIS.

First these two are free or you have to pay for comersial use? If yes what is the cost and what is the reliability for these application ?
Second i need to find locations on map using  (longitute and latidute) what is the best to choose?
Third which language is the best to use for write the interface , for each one ?

I have a created a custom map in Google Maps which has custom markers / pins.

I want to embed the map on my website so that my users can see the custom markers / pins, however when i embed that map, none of the pins show.

I've just noticed that the following message is displayed while you are creating the embed code:


This map is built for you

When you view this map on your site, you'll see your saved places on the map.

Your site's visitors won't see those saved places – they'll see a map built for them.

This seems pointless. Does anyone know a workaround for this? Thanks in advance for your help.
I need to find a mapping company which has maps that is not Google Maps. I would need to pay $10K if I planned to have more than 2,500 hits per day to the server, and that is too small for me.

What other choices are there for mapping?

I don't really need an API, except one which serves up the correct map.


GIS/GPS Programming

The Global Positioning System (GPS) is a space-based global navigation satellite system (GNSS) that provides reliable location and time information in all weather and at all times and anywhere on or near the Earth when and where there is an unobstructed line of sight to four or more GPS satellites. A geographic information system (GIS) or geospatial information system is any system that captures, stores, analyzes, manages, and presents data that are linked to location(s). In the simplest terms, GIS is the merging of cartography, statistical analysis, and database technology.

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GIS/GPS Programming