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Last modified: 28 September 2015


CIAO 4.2 to 4.3 upgrade guide

WCS support

  • Image data with a rotated tangent-plane projection are now displayed with North up (for both images and contours) rather than with the rotation as they were in CIAO 4.2.

  • The tangent-plane projection is the only supported WCS projection in CIAO 4.3 (in CIAO 4.2 the SIN projection was partly supported). Images and contours with a SIN projection can only be displayed in logical or physical systems.

  • Combining multiple plots or images with different coordinate systems in the same plot may not result in the same output.

Coordinate-system names

The algorithm used to generate the names of coordinate systems has changed. This means that data coordinate system names which used to look like plot2_ax1ay2 now look like ds. Since they can no-longer be guessed from the plot and axis names, the info_coordinate or info_current commands should be used to find out the name.

Info ordering

The order that objects are listed by the info and info_current commands may be different for those objects that are "children" of plots (so curves, histograms, contours, images and the annotations).

Last modified: 28 September 2015
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