René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Implementation missing for UGRID start_index attribute","articleBody":"The UGRID standard allows node connectivities to be specified as zero-based or one-based.  The base is indicated by the attribute `start_index` of the connectivity variable.  \r\n\r\n#### Code Sample, a copy-pastable example if possible\r\n\r\n```\r\n\tint mesh_element_node_connectivity(mesh_element, ungridded00004) ;\r\n\t\tmesh_element_node_connectivity:long_name = \"mesh_element_node_connectivity\" ;\r\n\t\tmesh_element_node_connectivity:standard_name = \"face_node_connectivity\" ;\r\n\t\tmesh_element_node_connectivity:start_index = 1;\r\n```\r\n\r\n#### Problem description\r\n\r\nCurrently, `psyplot` seems to handle only zero-based connectivities and disregards this attribute.\r\n\r\nOn the above example, an index-out-of-bounds error is thrown.\r\n\r\n#### Workaround\r\n\r\nAs a workaround, you can decrease the index by one\r\n\r\n```python\r\n    ds['mesh_element_node_connectivity'][:] = ds['mesh_element_node_connectivity'][:] - 1\r\n    ds['mesh_element_node_connectivity'].__setitem__('start_index',0)\r\n\r\n```\r\n\r\n#### NOTE\r\nThis is a bug report.\r\n\r\nFor requesting new features, use [this template](https://github.com/psyplot/psyplot/issues/new?template=new_feature.md\u0026title=NEW+FEATURE:).\r\n\r\nFor changing existing features, use [this template](https://github.com/psyplot/psyplot/issues/new?template=change_feature.md\u0026title=CHANGE+FEATURE:).\r\n","author":{"url":"https://github.com/platipodium","@type":"Person","name":"platipodium"},"datePublished":"2020-11-19T21:10:22.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/29/psyplot/issues/29"}