LONG/LAT INPUT

Input of LONG/LAT coordinates to non-EASI programs may be entered in a relatively free format. All the following examples will be evaluated to produce the same value (-110.258333 degrees longitude) and returned in a standard format (110d15'30.00" W).

 110d 15' 30.0" W
 110d15'30.0W
 110 15.5' W
 110.258333 W
-110.258333
 110 15 30 w
-110 15 30
w 30" 15' 110 d
w 15' 30  110 d

From the examples above, it can be seen that:

Alpha characters may be upper or lower-case.
Fields may be separated by one (or more) spaces.
The spacing may vary as long as fields of the same type do not abut. For example, "w15'30 110d" is valid as the following fields can be parsed:
1. the hemisphere (an alpha string)
2. a value of 15 (a numeric string)
3. the Minutes identifier (') (a character field). This identifies the preceding value as 15 Minutes.
4. a value of 30 (a numeric string). As no field identifier follows, this is assumed to be seconds, as the preceding field was a Minutes value.
5. a space as a field separator
6. a value of 110 (a numeric string)
7. the Degrees identifier (d) (an alpha string). This identifies the preceding value as 110 degrees.

Input of LONG/LAT coordinates to EASI programs depends on the type of parameter used:

Numeric parameters require decimal degrees. Longitudes would be in the range of -180.0 to 180.0 (in place of 180d W to 180d E). Latitudes would be in the range of -90.0 to 90.0 (in place of 90d S to 90d N). GEOSET uses numeric parameters UPLEFT and LORIGHT that would be subject to these conditions when MAPUNITS="LONG/LAT" or "LAT/LONG".

String parameters are more versatile and may take the various forms listed above.

Note: From EASI, the symbol for seconds (") should be omitted when specifying Longitudes or Latitudes, as this is interpreted as the end of the string and if there was a hemisphere after it would be ignored. For example PROLONG="110d15'30"W" would be incorrectly processed as 110.2583333 (rather than -110.2583333) from EASI. But PROLONG="110d15'30W" would be correctly processed. Another interface like Xpace does not run into this problem, as there is no "StartOfString" or "EndOfString" symbol, so either of the preceding examples would be evaluated correctly.