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confusing documentation for axis orientation

Open jjanuszkiewicz opened this issue 4 years ago • 0 comments

There are some inconsistencies and possibly errors in documentation related to axis orientation:

AxisOrientationEnum

AxisOrientationEnum.cs says that West is non-standard, but then goes to say that West is usually used and Easy is rare:

/// Orientation of axis. Some coordinate systems use non-standard orientations. 
/// For example, the first axis in South African grids usually points West, 
/// instead of East.

But:

    /// <summary>
    /// Increasing ordinates values go East. This is rarely used.
    /// </summary>
    East = 3,

    /// <summary>
    /// Increasing ordinates values go West. This is usually used for Grid X coordinates and Longitude.
    /// </summary>
    West = 4,

Wiki

Projecting points from one coordinate system to another says:

All transformations are done on double arrays, where the first value is primary axis (X/East/Latitude) and the second the secondary (Y/North/Longitude).

East should be Longitude, North should be Latitude. I'm not sure which coordinate should go first, but the example given on that Wiki page suggests that is should be longitude (120 is not a valid latitude value; this is assuming the example uses WGS84 or a similar system - this may be a wrong assumption):

double[] fromPoint = new double[] { 120, -3 };

jjanuszkiewicz avatar Aug 02 '21 10:08 jjanuszkiewicz