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- For programs downloaded as pre-built binaries, check the maintainer's website for a version compatible with Ubuntu 18.04.
- For programs downloaded as source and built by you, move the previous binaries (often in ~/bin or ~/.local/bin), then perform a clean build from existing (or updated) source code.
- For R packages, your local installations are in your ~/R directory. Rename that directory (e.g. to ~/R.previous) so you can refer to it to see which packages you installed, . You may then need to re-install those packagesany packages you need that are not already installed globally (you can check this by doing library(<module_name>) in R).
- For Python packages, your local installations are in your ~/.local/lib/python2.7 or ~/.local/lib/python3 directories. Rename those directories (e.g. to ~/.local/lib/python2.7.previous) so you can refer to it to see which packages you installed, then re-install those packages.
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