Versions Compared

Old Version 2

changes.mady.by.user Krista White

Saved on

compared with

New Version 3

changes.mady.by.user Krista White

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

Written by Michael Pavarini GPS data assignment

Edited by Krista White, GIS Support Specialist


The purpose of this assignment is to understand the procedure of getting data from a GPS unit into ArcMap. Collecting data in the field is a fairly simple process thanks to the advances that are continually being made to GPS devices. Getting the collected data to display in a GIS program takes a few steps. This assignment will demonstrate one method of converting the data taken directly from the GPS device to a workable format in ArcMap10.
Instructions:
Formatting

Format the GPS

...

Data in Excel

A One common way of downloading obtaining data points from a GPS device is to take download them off from the GPS unit and put them in an Excel tablespreadsheet. Once in Excel, the data must be manipulated to work with reformatted so that it will work in ArcMap.

  1. Download the sample Excel document "rawGPSdata" from the K drive. Open the file in Excel.
  2. Looking at Examine the four columns, you will see that each columns in the Excel file.  Each data point is assigned a unique identifier in the form of a number, has the date which it was collected, elevation data, and the coordinates of each point. The coordinate is coordinates are given in degrees (as an integer) and minutes (a real number). ArcMap handles coordinates the best when they are in Decimal Degree format; when .  In Decimal Degress, the entire coordinate string is a single, real number based on the degree. To convert from the original format Degrees and Minutes to Decimal Degree, we must first format the columns in Excel.Degrees, follow steps 3-
  3. Select the entire E column in the "rawGPSdata" file (containing the location)
  4. Click on the "Data" tab on the top toolbar.
  5. Image Removed In  In the "Data Tools" box, select the "Text to Columns" tool. The Text to Column Wizard will allow you to separate the coordinate information into separate columns.
  6. Select "Fixed Width" and hit "Next>"

    Image Added

  7. We must separate the N and W from the degree column. To do this, click between the "N" and "40" and between "W" and "74." Then hit "Next>Next →"

...

  1. \\!SDC_Images^DecDegConvertTexttoColumns.png|thumbnail,align=center!
  2. Do not make any changes in step 3 of the Wizard. Just hit "Finish" to exit.
  3. You will see that the single coordinate column has now been divided into 6 separate columns.
  4. The idea now is to isolate the latitude and longitude components each into a single column. At this stage it is best to reorganize the columns.
  5. Clear the contents of the "E" and "H" columns by right clicking on the columns and selecting "Clear Contents." The coordinate information should now exist in two sets of columns with space in between them.

...