greta

• outer() (and %o%) now works with greta arrays when FUN = "*", instead of silently returning a base array of NAs; base R's "*" fast path used as.vector(), which dropped the greta operation (#582).

Installation and dependencies

• greta now resolves its Python environment more flexibly instead of always forcing reticulate's managed (uv) environment: it respects a user-set RETICULATE_PYTHON, a stored greta preference, or an existing greta-env-tf2 conda environment, and otherwise uses the managed (uv) environment (#801).
• The managed (uv) backend now works without an internet connection, by enabling uv's offline mode (via environment variable UV_OFFLINE) once reticulate's uv cache is installed. You can set UV_OFFLINE=0 (or =1) yourself to force online or offline resolution, respectively (#814).
• Fixed library(greta) failing with an error when greta's stored Python preference file exists but is empty (#809).
• greta_deps_spec() now only checks that the requested TensorFlow version is one greta supports (TensorFlow 2.16 and later are not supported, as they ship Keras 3); compatible TensorFlow Probability and Python versions are left to uv or conda to resolve rather than being validated against a fixed compatibility table (#675).
• greta_list_py_modules() shows the Python packages installed in a specific TF2 environment (#801, #809).
• greta_remove() consolidates greta's Python removal helpers behind a single what argument to remove the greta-env-tf2 conda environment, miniconda, reticulate's uv cache, the stored Python preference, the stored dependency versions, or all of them. This means destroy_greta_deps(), greta_remove_all_deps(), remove_greta_env(), remove_miniconda(), and remove_reticulate_uv_cache() are now superseded by greta_remove() (#814).
• greta_remove() no longer leaves a stale, deleted environment active for the rest of the session: it now invalidates greta's cached Python backend and nudges you to restart R if you try to use greta again without restarting, instead of silently failing or falsely reporting the removed environment as still available.
• greta_set_deps() persistently chooses which TensorFlow, TensorFlow Probability, and Python versions greta uses; the managed (uv) environment installs them on next load and install_greta_deps() uses them as its default; clear with greta_remove("deps") (#817).
• greta_set_python() and greta_reset_python() let you choose, persistently, which Python environment greta uses - the managed (uv) environment (backend = "uv", the default), a conda environment (backend = "conda"), or a specific Python (backend = "path"); each reports the stored preference, warns if RETICULATE_PYTHON takes precedence, and shows what greta will resolve to on its next load (#801, #809, #817).
• greta_set_python("path", path = ...) accepts either a Python binary or an environment directory (a virtualenv or conda prefix), looking for bin/python (or Scripts/python.exe on Windows) inside it, which eases offline and pre-installed setups (#814).
• greta_sitrep() now reports the resolved Python backend and whether greta can start offline: for the managed (uv) environment, the UV_OFFLINE setting and whether reticulate's uv cache is populated; a missing conda environment is reported neutrally as "not used" on the managed (uv) backend rather than as a failure (#801, #817).
• greta_sitrep() now requires Python 3.9 or later (previously 3.8), matching the Python versions greta supports (#809).
• install_greta_deps() now records the location of the greta-env-tf2 conda environment at install time, so greta auto-detects it in any conda installation, not just reticulate's miniconda (#809).
• install_greta_deps() is no longer required for most users, as greta now installs TensorFlow and TensorFlow Probability automatically via uv on first use; it remains for installing a conda environment (for example, for offline use), which you can then select with greta_set_python("conda") (#801).
• install_greta_deps() now restores the warning.length option when it exits, instead of leaving its own value in place for the rest of the session.
• reinstall_greta_env() and reinstall_miniconda() are now deprecated in favour of reinstall_greta_deps() (#814).
• remove_greta_env(), remove_miniconda(), and remove_reticulate_uv_cache() ask for confirmation before removing, gain an ask argument (default interactive()) so they work non-interactively, and invisibly return whether anything was removed (#809).
• remove_reticulate_uv_cache() removes reticulate's uv cache; note this cache is shared by all reticulate packages and is not greta-specific, and a system-wide uv cache is left untouched (#801, #809).