Modify install_prereqs to create a venv

Modify the macOS install_prereqs script used for Drake tarball
installations to create a Python virtual environment in the location
where Drake has been extracted. Also use this to install Drake's Python
dependencies using PDM. Update user documentation accordingly.

This means we are now using the pinned versions of our dependencies and
are no longer keeping a duplicate copy of this list solely for
installations.

This also means that we are installing a pinned numpy in the venv for
installations. This was already the case for source builds, but means we
now no longer have any reason to install numpy from Homebrew, so remove
it from there.

doc/_pages/from_binary.md

@@ -66,6 +66,8 @@ Download the binary release ``*.tar.gz`` file, using one of the links above.
 In the example below, we'll use ``drake.tar.gz`` to refer to it, but your
 download will have a more version-specific filename.
 
+#### Ubuntu
+
 Create and activate the environment:
 
 ```bash
@@ -77,11 +79,32 @@ source env/bin/activate
 
 Install dependencies within the environment:
 
+```bash
+sudo env/share/drake/setup/install_prereqs
+````
+
+Refer to [Quickstart](/installation.html#quickstart) for next steps.
+
+#### macOS
+
+Create the environment:
+
+```bash
+mkdir -p env
+tar -xvzf drake.tar.gz -C env --strip-components=1
+```
+
+Install dependencies within the environment:
+
 ```bash
 env/share/drake/setup/install_prereqs
 ````
 
-(On Ubuntu, the script might ask to be run under ``sudo``.)
+Activate the environment:
+
+```bash
+source env/bin/activate
+```
 
 Refer to [Quickstart](/installation.html#quickstart) for next steps.
 

setup/BUILD.bazel

@@ -7,7 +7,6 @@ package(default_visibility = ["//visibility:public"])
 # downstream projects.
 exports_files([
     "mac/binary_distribution/Brewfile",
-    "mac/binary_distribution/requirements.txt",
     "mac/source_distribution/Brewfile",
     "mac/source_distribution/Brewfile-doc-only",
     "mac/source_distribution/Brewfile-maintainer-only",
@@ -44,7 +43,9 @@ install_files(
         "//tools/cc_toolchain:apple": [
             "mac/binary_distribution/Brewfile",
             "mac/binary_distribution/install_prereqs.sh",
-            "mac/binary_distribution/requirements.txt",
+            "python/pdm.lock",
+            "python/pyproject.toml",
+            "python/requirements.txt",
         ],
         "//tools/cc_toolchain:linux": [
             "deepnote/install_nginx",
@@ -58,6 +59,7 @@ install_files(
     strip_prefix = [
         "mac/binary_distribution",
         "ubuntu/binary_distribution",
+        "python",
     ],
     rename = {
         "share/drake/setup/install_prereqs.sh": "install_prereqs",

setup/mac/binary_distribution/Brewfile

@@ -9,7 +9,6 @@ brew 'fmt'
 brew 'glib'
 brew 'graphviz'
 brew 'ipopt'
-brew 'numpy'
 brew 'pkg-config'
 brew '[email protected]'
 brew 'spdlog'

setup/mac/binary_distribution/install_prereqs.sh

@@ -67,5 +67,10 @@ if ! command -v pip3.12 &>/dev/null; then
 fi
 
 if [[ "${with_python_dependencies}" -eq 1 ]]; then
-  pip3.12 install --break-system-packages -r "${BASH_SOURCE%/*}/requirements.txt"
+  readonly setup="${BASH_SOURCE%/*}"
+  readonly venv_root="$(cd "${setup}/../../.." && pwd)"
+  python3.12 -m venv "${venv_root}"
+  "${venv_root}/bin/pip3" install -U -r "${setup}/requirements.txt"
+  "${venv_root}/bin/pdm" use -p "${setup}" -f "${venv_root}"
+  "${venv_root}/bin/pdm" sync -p "${setup}" --prod
 fi

setup/python/pyproject.toml

@@ -15,13 +15,11 @@ name = "drake"
 requires-python = ">=3.10"
 
 # Dependencies needed to build Drake.
-#
-# WARNING for Drake Developers: This list must be kept in sync with
-# setup/mac/binary_distribution/requirements.txt.
 dependencies = [
     "ipywidgets",
     "matplotlib",
     "notebook",
+    "numpy",
     "Pillow",
     "pydot",
     "PyYAML",