g.transform(1)

NAME
g.transform

DESCRIPTION
g.transform is an utility to compute transformation based upon GCPs and output error measurements.

NOTES
For coordinates given with the coords file option or fed from stdin, the input format is "x y" with one coordinate pair per line.

The transformations are:

order=1:
    e = [E0 E1][1].[1]
        [E2 0][e] [n]

    n = [N0 N1][1].[1]
        [N2 0][e] [n]
order=2:
    e = [E0 E1 E3][1 ] [1 ]
        [E2 E4 0][e ].[n ]
        [E5 0 0][e&sup2;] [n&sup2;]

    n = [N0 N1 N3][1 ] [1 ]
        [N2 N4 0][e ].[n ]
        [N5 0 0][e&sup2;] [n&sup2;]
order=3:
    e = [E0 E1 E3 E6][1 ] [1 ]
        [E2 E4 E7 0][e ].[n ]
        [E5 E8 0 0][e&sup2;] [n&sup2;]
        [E9 0 0 0][e&sup3;] [n&sup3;]

    n = [N0 N1 N3 N6][1 ] [1 ]
        [N2 N4 N7 0][e ].[n ]
        [N5 N8 0 0][e&sup2;] [n&sup2;]
        [N9 0 0 0][e&sup3;] [n&sup3;]
["." = dot-product, (AE).N = N'EA.]

In other words, order=1 and order=2 are equivalent to order=3 with the higher coefficients equal to zero.

SEE ALSO
i.rectify

AUTHORS
Brian J. Buckley
Glynn Clements
Hamish Bowman

Last changed: $Date: 2011-11-08 12:29:50 +0100 (Tue, 08 Nov 2011) $

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