Which coordinate system to select when importing Shapefiles into iCMTGIS PRO?

When loading geographic position data into a mapping software program, the program needs to know which coordinate system the position data refers to.

When you import such position data into iCMTGIS PRO, it will display a window for you to specify the datum, coordinate system and distance unit so that it can place the geographic Features (shapes) in the correct map location.

Often the set of Shapefiles that you get comes with a .prj (projection) file. If you include this file with the files you copy to the Documents folder for iCMTGIS PRO, then when you import the Shapefiles, the app will display the proper coordinate system information, and all you need to do is to confirm it. You might want to write down this information if you don’t already know it.

Suppose you knew the reference coordinate system beforehand, and you have set the coordinate system in iCMTGIS PRO to match it before importing the Shapefiles, then the imported data will be displayed using that coordinate system.

On the other hand, if the working coordinate system is different from that used by the Shapefiles, then after the Shapefiles have been imported, the data will be displayed using the working coordinate system.

In other words, when you specify the coordinate system during the import process, it is strictly for use in interpreting the imported data. It does not change the currently active coordinate system.

Therefore, if you did not know the coordinate system information of the Shapefiles, you should write down the information displayed by iCMTGIS PRO during the import process, so that you could switch to that system later, if you wish.

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Shapefiles for Chile shows up in North America

“We update de FORESTER GPS GIS II, on iPad from version 1.0.1 to 1.0.2 and we are having issues with the coordinate system when importing a shape file.The shape appears in North América and we are from Chile. We use UTM with Datum WGS84. Is there any suggestion on what can we do. I try this in two different devices with the new version and both have the same problem. When using it in the 1.0.1 version all goes OK.”

Please make sure you have selected the correct UTM Zone.

Please also copy the .prj file for the Shapefiles to the documents folder for Forester GPSGIS II.

What coordinate system do the Shapefiles use? If they are based on WGS 84 LLA, then try setting the Forester GPSGIS II to that coordinate system before importing the Shapefiles. After importing the Shapefiles, then change the coordinate system to UTM WGS84.

iCMTGIS PRO for electric pole staking

“So what I’m needing is software that can collect a start and end point for a new line and then take those and tell me where along that line to set my electric poles in order to keep them nice and straight in line with the starting and ending pole. Also it would need to be able to route me say 90 degrees from one point across the road to another pole 65 feet away (for example). Then if I could take these points and load them into Arc GIS as points to snap to, where I could then use my staking application to draw the new lines on the map at these points.”

Yes, iCMTGIS PRO along with the EOS Sub-cm GPS receiver will enable you to achieve what you have in mind.

1. Data Collection

You can use the GPS – Collect function in iCMTGIS PRO to record the start and end points then create the Line Feature.

2. Line Stakeout

The GPS – Line Stakeout function in iCMTGIS PRO will help you stay on the straight line and display your distance from the starting point. This will allow you to set a pole at a specific distance from the staring point. The app also provides a function to let you store the position of the pole. There is a tolerance setting in the Stakeout function that will issue beeps and flash a “Target” message as long as you are within range.

3. Traverse and Point Stakeout

“Also it would need to be able to route me say 90 degrees from one point across the road to another pole 65 feet away (for example).”

The GPS – Collect – Traverse function in iCMTGIS PRO will let you occupy an existing point and create a new point based on distance and angle (bearing or azimuth). Then you can use the GPS – Point Stakeout function to help you get to the new point.

If that “other pole” already exists as an imported point, then you will simply use GPS – Point Stakeout to get to it.

In fact, I would incorporate the point representing that other pole or any other location in the Line Feature mentioned in Step 2 above. In other words, you would create your entire “route” as a single Line Feature (no matter how many bends there are) then use the Line Stakeout function throughout.

4. Digitization

You can draw Points, Lines and Areas within iCMTGIS PRO. You can export these Features to Shapefiles to use in other apps. You can also import Points, Lines and Areas from Shapefiles.

“Would one of your less expensive apps do some of the tasks I talked about in my first email just to try it out?”

The Stakeout iCMT app is very cost effective for performing the point and line stakeout tasks. What it does not provide, among others, are the GPS – Collect function and the GPS – Traverse function. In addition, it gets the GPS position from the Apple CoreLocation, which is not as accurate as the GPS position that iCMTGIS PRO gets directly from the EOS GPS receiver in the “Enable External GPS receiver” mode.

The Stakeout iCMT app will be great to use for a practice run of your stakeout operation or for training your employees.

Shapefiles too large. Is there a way to allocate larger memory to RAM?

It is nice that many government agencies provide GIS data in Shapefile format. However, if they pack a lot of data into one large file, certain computer systems are unable to load the data. For example, your state may provide the land parcel numbers and the associated information such as owners and LAT-LON coordinates for all the counties in one set of Shapefiles totaling about 1 GB. If your iPAd only provides 512 MB or 1 GB of RAM, you will not be able to load these Shapefiles into the GIS app.  You will likely not be able to load them into a unit with 2 GB RAM, either. This is because memory space is needed for storing the files as well as running them.

You can check the RAM size of your iPad by going to this WIKIPEDIA article on iPad and selecting “4. Model Comparison”.
There is no way for you to allocate some storage memory of your iPad to the RAM.

If you have PC-GIS, then you could load the Shapefiles into this PC software program, then select just the land parcel(s) of interest to you and copy them to a new PC-GIS job file. Within PC-GIS, you could remove some of the Attributes that you don’t need. Then you can save the job data to a .pmp file for use in your CMT iOS app. Or you could export the pared down data to Shapefiles for use in some other GIS system.

Stakeout iCMT for trailblazing

“I’m wondering if your software has the capability to allow a user to navigate to a location based on a set of coordinates. . . . The problem is that ArcPad is not designed to allow users to navigate to a set of points and I cant find anything else that will easily allow a user to do this, either. Through internet research, I discovered a reference to your iPhone app Stakeout iCMT. Before I recommend a purchase for this, could you tell me some more about the product? Will it show the tractor driver the location of the next point in our shapefile so that he would see distance and direction to get within 10-15 feet of that point? Please note the driver will NOT have to collect any data in the field he is merely using the program to show him how to drive the tractor in order to create a walking trail (which is NOT a straight line) through dense terrain.”

Stakeout iCMT will allow a user to navigate to a location based on a set of coordinates. It can also help the user to stay on course on a design line.

Stakeout iCMT can be used on an iPhone or an iPad. The iOS devices do not provide good GPS accuracies. You could use an external Bluetooth GPS receiver that is compatible with iPhone or iPad, such as a Bad Elf GPS or a Dual XGPS-150A, which claim 1-3 meters accuracy. There are more accurate GPS receivers available, which cost much more.

Stakeout iCMT is probably the least expensive but really powerful software solution for your task at hand. You can import your Shapefiles then use Stakeout iCMT in one of the following ways:

1. If you want the driver to go from one design point to the next, then create a Line Feature by using Add Line Manually and snapping to the points in the desired order. Then use Line Stakeout to go from one node to the next on the line shape.
You can set the distance tolerance for the app to notify you when you get within that distance from the current target point.

2. You could import the Line shape for the desired path through the woods. Then you would use the Line Stakeout function and let the app help you stay close to the line all the time. The Line Stakeout function will display your distance to the line all the time. And if you set a distance tolerance, then the app can keep on beeping as long as you are within the tolerance distance from the line.

We also have several other apps that incorporate the Stakeout functions along with other functionality.

Questions about Wetland – Stakeout 1.0.1 beta-test version

“I have been going through the program and so far it is exactly what we have been looking for! “

This user submitted a few relevant questions that may be of interest to other users/testers of this app. The questions and answers are posted below.

1. “Is there a way to use the trimble data with the program? We want the accuracy of the Trimble if we can somehow use that data instead of the data collected by the gps in the ipad. “

If you can export the data collected using the Trimble data collector in Shapefiles format, then you can copy these Shapefiles to the Documents folder for the Wetland – Stakeout app then import them into the Wetland – Stakeout app.

2. “Do you have a way to associate photos with the waypoints?”

The current release of Wetland – Stakeout app does not provide the function to attach photos to a waypoint. However, you can include one or more photos in a report form that you prepare using Wetland – Stakeout. We will add the function to attach photos to a Feature in the next release.

3. “…. the wetland determination form for the AGCP. In the hydrology section on the first page all of the primary indicators are listed but not all are available on the right side of the split screen where I select them. Is this something that is resolved in the paid/full version?”

If you hold the iPad in Portrait orientation, you will see all the check boxes. When you hold the iPad in Landscape orientation, please swipe to the left to see the remaining check boxes.

4. “Also, in the same section under ‘Field observations’ when these are populated the section to the right labeled ‘Wetland hydrology present’ also will populate based on what field observations are checked. Is this something that happens in the full version?”

With respect to “Wetland hydrology present”, the result sometimes depends on other additional user observations. Therefore, we leave it up to the user to mark the appropriate box.

Sweden needs help

“We are trying your app iCMTGis II for ipad but we use the coordinate system SWEREF99TM is it possible for us to project in this system so that we can use our own shapefiles from ArcGiS, i.e. do your program convert shapefiles or do we need to change the coordinate system and how do we do it? Secondly we have major difficulties to import shapefiles, eventhough we can see them in the app in Itunes, they do not show up in the import.”

1. Coordinate system
In ArcGIS, please switch to a standard coordinate system (such as LLA or UTM) then export the Shapefiles. In iCMTGIS II, set the coordinate system to be LLA or UTM accordingly. Then import the Shapefiles into iCMTGIS II.

If you wish to use the SWEREF99TM in iCMTGIS II, you could use our PC-GIS PRO 09 software to set up a user-defined coordinate system then copy the user_cor.sys file (with the file name in lower-case letters) from your PC to the documents folder for iCMTGIS II on your iPad device.

2. Shapefiles import
Please make sure all the associated files have been copied to the Documents folder for iCMTGIS II (*.shx, *.shp, *.dbf, *.prj). The file names should be in lower-case letters and numbers. The procedure for importing Shapefiles are discussed in our blog article at:
http://wp.me/p1v4kh-lu

Also, please check your iCloud setting under Main Menu/Setup.
If the check box for Job is marked, the app will look for the .pmp job files and the Shapefils in iCloud storage. To see the files in your local documents folder, please un-mark this check box then tap the OK button.

The above information also applies to the iGPSGS II app for use on the iPhone.