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https://issues.apache.org/jira/browse/SIS-427?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Martin Desruisseaux updated SIS-427:
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Description:
The Mollweide projection added by SIS-426 is not _surjective_: not all (_x_,
_y_) values can be mapped to a (_latitude_, _longitude_) values. Consequently
current implementation of {{CRS.suggestCommonTarget(…)}}, which is to suggest
converting projected coordinates to geographic coordinates, may not work for
Mollweide. For that projection, it may be more reliable to convert geographic
coordinates to projected coordinates.
For allowing {{CRS.suggestCommonTarget(…)}} to make a better choice, we need to
know more about the {{MathTransform}} properties. One approach would be to add
a {{MathTransform.getFunctionProperties()}} method which would return an
{{Set<FunctionProperty>}}. This set can tell us if the function is invertible,
injective, surjective or bijective.
was:
The Mollweide projection added by SIS-426 is not _surjective_: not all (_x_,
_y_) values can be mapped to a (_latitude_, _longitude_) values. Consequently
current implementation of {{CRS.suggestCommonTarget(…)}}, which is to suggest
converting projected coordinates to geographic coordinates, may not work for
Mollweide. For that projection, it may be more reliable to convert geographic
coordinates to projected coordinates.
For allowing {{CRS.suggestCommonTarget(…)}} to make a better choice, we need to
know more about the {{MathTransform}} properties. One approach would be to add
a {{getFunctionProperties()}} method which would return an
{{Set<FunctionProperty>}}. This set can tell us if the function is invertible,
injective, surjective or bijective.
> Improve CRS.suggestCommonTarget(…) by allowing to know Set<FunctionProperty>
> ----------------------------------------------------------------------------
>
> Key: SIS-427
> URL: https://issues.apache.org/jira/browse/SIS-427
> Project: Spatial Information Systems
> Issue Type: Improvement
> Components: Referencing
> Reporter: Martin Desruisseaux
> Assignee: Martin Desruisseaux
> Priority: Major
>
> The Mollweide projection added by SIS-426 is not _surjective_: not all (_x_,
> _y_) values can be mapped to a (_latitude_, _longitude_) values. Consequently
> current implementation of {{CRS.suggestCommonTarget(…)}}, which is to suggest
> converting projected coordinates to geographic coordinates, may not work for
> Mollweide. For that projection, it may be more reliable to convert geographic
> coordinates to projected coordinates.
> For allowing {{CRS.suggestCommonTarget(…)}} to make a better choice, we need
> to know more about the {{MathTransform}} properties. One approach would be to
> add a {{MathTransform.getFunctionProperties()}} method which would return an
> {{Set<FunctionProperty>}}. This set can tell us if the function is
> invertible, injective, surjective or bijective.
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