Introduction
X-pos provides Coordinate Transformation service for users who wish to convert WGS84 coordinates to a different target coordinate system.
This service can be accessed via the “Post-Processing > Transformation” page on the SBC Portal. Here, users can upload input coordinate files, select a target coordinate system from those made available after upload by administrators, and trigger the transformation.
Currently, only Cartesian WGS84 coordinates are accepted as input.
Only users with a suitable subscription can benefit from the Coordinate Transformation service. In SBC, this is granted by the “Coordinate Transformation” product. Please note that the Transformation option is only visible on the SBC Portal if the “Enable Coordinate Transformation Service” slider is toggled on the Settings > X-pos > General page.
If no subscription is available for the transformation service, users will not see the “Transformation” entry in the left navigation menu. The “Transformation” page will not be available in the SBC Portal and there will be no corresponding tab on the ““Post-Processing > Results” page.
Input Format
The supported input format for Coordinate Transformation is CSV. Multiple files can be uploaded.
Each line in the CSV text file represents a point to be transformed.
The following input schemas are supported:
<Point name>;<Cartesian X>;<Cartesian Y>;<Cartesian Z>;<M0>;<Q11>;<Q12>;<Q13>;<Q22>;<Q23>;<Q33>
<Point name>;<Cartesian X>;<Cartesian Y>;<Cartesian Z>;<DeltaX>;<DeltaY>;<DeltaZ>
<Point name>;<Cartesian X>;<Cartesian Y>;<Cartesian Z>
The following constraints apply:
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The CSV file must not contain any header lines.
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A semicolon must be used as the separator.
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All fields must be completed.
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Coordinates must be expressed as Cartesian WGS84 coordinates in metres.
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The point must be used as the decimal separator for numbers.
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If the full covariance matrix is provided, it is utilised during the transformation process. Delta values are supported as input but are ignored during the transformation process.
Sample of supported input coordinate file:
VILL;4849833.7962;-335049.1807;4116014.8247
MAJU;-6257572.5057;950332.3662;785215.1556;0.0002;0.0001;0.0002
P001;-3956200.6462;3349499.6179;3703990.1373
P002;4263850.7413;722550.4069;4672974.3289;0.27439910;0.00000071;0.00000010;0.00000042;0.00000020;0.00000005;0.00000097
Validation Checks
Several validations are in place every time a user uploads input files for coordinate transformation. These cover:
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Exceeding the maximum size allowed (150 MB).
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The wrong format of the uploaded file(s), since only the CSV format is supported.
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Incorrect content of the uploaded file, if its structure does not comply with the above.