Unit Converter

The Unit Converter dialog provides quick conversion between units and values used in coordinate system parameter boxes.

Launch the Unit Converter dialog by pressing the 123 button next to a parameter in the Coordinate System dialog or next to the Local Scale or Local Offset boxes in the Coordinate System Metrics dialog, and then choose Unit Converter.

<unit>	Choose the unit of measure to be converted into the unit of measure used by the coordinate system.
Original	Specify the number of units selected to be converted.
Result	The converted value, in the units used by the coordinate system, of the specified number of units to be converted.
OK	Apply the converted Result value to the box for which the Unit Converter dialog was launched.

Example

We are working with a coordinate system, such as Orthographic, which uses meters as the units. The metadata for the data set we are using specifies we must use X and Y local offsets of 200 US Survey feet. We need to convert that value in US Survey feet into the equivalent number of meters.

We press the Unit Converter button next to the Local offset X box.

In the menu we choose Unit Converter.

The dialog launches with Meter as the unit. From the long pull down list in the uppermost, units box we choose US Survey Foot.

We enter 200 into the Original box. The dialog automatically converts that into 60.960... meters in the Result box. We press OK.

The Local offset X box is automatically populated with the computed result value of 60.960... meters. If we want the same offset in the Local offset Y box we can either repeat the above procedure for the Y box or simply copy and paste the value from the X box.

Notes

Metrics values - Choosing a coordinate system in the main Coordinate System dialog will load the Coordinate System Metrics parameters with the correct values for the chosen system. Those are usually based on a unit of 1 meter or 1 degree, but some national coordinate systems use values like 0.9 meter. Custom values as read from a world file or entered manually will also appear.

EPSG and SRID Overrides - EPSG and SRID coordinate systems use a numeric code to identify the coordinate system. Metrics for EPSG and SRID coordinate systems are applied as overrides. This allows keeping the coordinate system definition as a code for readability and for easier conversion.

List all units of measure - Transform templates often provide parameter boxes that have a list of all available units of measure, and coordinate system dialogs often do as well. However, if we would like a list of all units of measure available we can use SQL:

TABLE CALL CoordUnits();

or more elegantly, with a field that indicates if the unit of measure is a radial unit suitable for latitude/longitude coordinate systems:

SELECT

StringJsonValue([value], 'Unit', true) AS [name],

Coalesce(StringJsonBoolean([value], 'UnitLatLon', true), false) AS [latlon]

FROM CALL CoordUnits();

Unit Converter

Example

Notes

See Also