GPS to GIS Creating Tables to Import (instructions for MS Excel)

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Use the directions below to enter the data into an Excel spreadsheet and prepare to import it into a GIS.

Note: Much of this material is also covered in this Powerpoint presentation: Converting Coordinates.

Enter your data into a Microsoft Excel spreadsheet or another database or spreadsheet program that can produce database or delimited text files. I prefer a format like the one shown here and in Entering Data Example. This illustration shows point data for trees located in a park. Note that the degrees and minutes are in separate columns; you will not need to separate them if your data are already in decimal degrees. This format also encourages you to understand the positive/negative notation to indicate hemisphere (see highlighted cell).

Convert your data. If your data are not in a form that GIS software will understand, you will need to convert. You can use Excel or a similar program to perform the conversion. In the example here (see also Convert Data Example and Practice Converting Data), the same tree data are being converted from decimal minutes to decimal degrees. Note the highlighted cell; the conversion formula appears in the formula bar next to the "=" sign. The decimal minutes (B2) are divided by 60, the result is added to the degrees of longitude (A2), and this result is multiplied by -1 (C2) because we are in the Western Hemisphere.

Prepare your database file. Now you can make a spreadsheet to import as an event theme into your GIS software (see Data To Import). Copy and paste the values only from the x_coord, y_coord, and z_coord fields and all of the attribute data into a new spreadsheet file. Remember that the GIS software will not read the formulas.

Be sure to format the cells that hold the x and y coordinates as numbers with four or more decimal places. Excessive rounding dilutes to accuracy of your data.

 Now select all cells with data or fieldnames and save the new spreadsheet in dBASE IV or delimited text format.

You are now ready to import your data into a map. Select your GIS software below for instructions on importing your table.

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