Basemap fails with Mollweide projection across prime meridian or negative longitude defining both central meridian and range about gmt HOT 5 CLOSED

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The equivalent GMT commands also fail. So I'm transfering the issue to the upstream GMT repository. The equivalent GMT commands are:

gmt basemap -Jw-30/0.1 -R-100/-10/0/90 -Bafg -pdf fig4
gmt basemap -Jw-30/0.1 -R-100/20/0/90 -Bafg -pdf fig5
gmt basemap -Jw330/0.1 -R-100/20/0/90 -Bafg -pdf fig6

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The actual need I have is to create a map in a Molleweide projection defined by a central meridian west of 0 longitude and with a range that spans across 0 longitude.

Thanks @thomasAmorrow for your detailed report! I can reproduce this issue with GMT 6.5.0, but it worked with GMT 6.4.0. The analogous issue occurs with the Hammer (H) projection. The projections N, Kf, Ks, I, and R seem to work.

Depending on how fast you need this map and if you do not need any features or bug fixes of GMT 6.5.0, you may want to consider setting up a conda environment with PyGMT and GMT 6.4.0 (, even it is generally recommended to use the latest versions).

For me, the following code works with GMT 6.4.0, but fails with GMT 6.5.0 (the same holds for the equivalent GMT commands by @seisman in comment #8403 (comment)):

import pygmt

dict_J_R = {
    "0/180/0/90": "W30/10c",  # Works
    "-180/0/0/90": "W-30/10c",  # Fails with GMT 6.5.0
    "-20/180/0/90": "W30/10c",  # Works
    "-180/20/0/90": "W-30/10c",  # Fails with GMT 6.5.0
}

fig = pygmt.Figure()

for panel in dict_J_R.keys():
    fig.basemap(
        region=panel,
        projection=dict_J_R[panel],
        frame=["afg", f"+tJ={dict_J_R[panel]}, R={panel}"],
    )
    fig.shift_origin(xshift="+w+1c")

fig.show()
# fig.savefig(fname="mollweide_subregion.png")

Output figure:

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Hmm, we are having an issue with central longitudes in [0 360] and regions in [-180 180]. For some reason the central longitude is converted to [0 360] and a test saying

/* For regional (<360) areas we cannot have clon > 180 away from either boundary */

fails. For the moment the solution is to give the -R in [0 360]. e.g., this works

gmt basemap -Jw-30/0.1 -R260/350/0/90 -Bafg -png lixo

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