Surfer 13 and previous versions cannot convert lat/lon data in DMS format to decimal degrees automatically. However, converting data from DMS format into decimal degrees is actually quite easy and can be done on a calculator, in Excel or in the Surfer worksheet.
Consider the latitude value 39° 25' 30". This value needs to be converted from the current DMS format into decimal degrees to use it in Golden Software programs. There are 60 minutes in one degree and 3600 seconds in one degree. To convert minutes and seconds to decimal degrees, divide minutes by 60, divide seconds by 3600, and then add the results to obtain the decimal equivalent. Use the following formula to make the conversion:
Decimal degrees = Degrees + (Minutes/60) + (Seconds/3600)
For Example, to convert 39° 25' 30" to decimal degrees
- First, convert minutes and seconds to their degree equivalents and add the results
25'/60 = 0.4167°
30"/3600 = .0083°
0.4167° + 0.0083° = 0.425°
- Then, add this number to the number of degrees.
39° + 0.425° = 39.425°
- So, the final result is:
39° 25' 30" = 39.425°
Once your coordinates are in decimal degrees, you can use the data in Surfer.
To perform this conversion automatically in the Surfer worksheet, upgrade to the current version.