Merge remote-tracking branch 'origin/release'

Add MATCENTERING special matrix type.

Update index.rst

Merge branch 'psanan/docs-fix-links-2021-04-28' into 'release'

Docs: fix some broken links

See merge request petsc/petsc!3928

Docs: fix some broken links

HDF5: Improve timestepping.

* add PetscViewerHDF5{Push,Pop,Is}Timestepping to control timestepping mode
* write timestepping attribute for datasets and check it on reading
* fail gracefully if tryin

HDF5: Improve timestepping.

* add PetscViewerHDF5{Push,Pop,Is}Timestepping to control timestepping mode
* write timestepping attribute for datasets and check it on reading
* fail gracefully if trying to read non-timestepped dataset in timestepping mode and vice-versa (fix #425)
* rewrite src/vec/vec/tutorials/ex19.c to improve coverage for timestepping testing

show more ...

Merge remote-tracking branch 'origin/release'

Merge branch 'psanan/docs-dev-changes-to-sphinx' into 'main'

Docs: move development changes to Sphinx

Closes #879

See merge request petsc/petsc!3926

Docs: fix 3.15 changes title

Merge remote-tracking branch 'origin/release'

Docs: move development changes to Sphinx

Merge branch 'psanan/docs-warning-cleanup-2021-04-23' into 'release'

Docs: silence some Sphinx warnings

See merge request petsc/petsc!3912

Merge branch 'psanan/docs-conf-py-extensions-cleanup' into 'release'

Docs: conf.py extensions cleanup

See merge request petsc/petsc!3906

Merge branch 'psanan/docs-venv-metadocs' into 'release'

Meta-docs: instructions on using a Python 3 virtual environment, minor cleanups

See merge request petsc/petsc!3914

Docs: silence some Sphinx warnings

Docs: remove logic and instructions for ReadTheDocs

Merge remote-tracking branch 'origin/release'

update petsc4py doc wrt download-petsc4py -> with-petsc4py=1

Merge remote-tracking branch 'origin/release'

Add PetscSF paper to front-page news

Meta-docs: remove example of list-table

This example is included in the linked docutils docs,
so remove it in the interst of making the meta-docs shorter and thus
more likely to be read.

Meta-docs: move footnote to end

Meta-docs: local docs build instructions with Python 3 virtual environment

Docs: add last updated time and git-describe string to page footers

This is done using settings available from the pydata theme.

This includes a template 'last-updated.html', which references
an in

Docs: add last updated time and git-describe string to page footers

This is done using settings available from the pydata theme.

This includes a template 'last-updated.html', which references
an internal 'last_updated' which is controlled by
'html_last_updated_fmt' in conf.py.

The date/time is intended to be ISO 8601 compliant.

show more ...

Merge remote-tracking branch 'origin/release'