FIX snapML error

solvers/snapml.py

@@ -11,7 +11,14 @@ class Solver(BaseSolver):
     name = "snapml"
 
     install_cmd = "conda"
-    requirements = ["pip:snapml"]
+
+    # Snap ML wheels are built with numpy 1.*, they are not compatible with
+    # numpy>=2. TODO : upgrade numpy when compatible wheels are released.
+
+    # libomp x86_64 and Homebrew are needed for snapML to work correctly on
+    # MacOS. Please check this tutorial to install SnapML correctly:
+    # https://github.com/benchopt/benchmark_ridge/blob/tutorials/snapml_macos.rst
+    requirements = ["numpy'<2'", "pip:snapml"]
 
     parameters = {"gpu": [False, True]}
     references = [

test_config.py

@@ -13,3 +13,9 @@ def check_test_solver_install(solver_class):
 
     if "glmnet" in solver_class.name.lower():
         pytest.xfail("glmnet produces discrepancies (see issue #2).")
+
+    # libomp x86_64 and Homebrew are needed for snapML to work correctly on
+    # MacOS. Please check this tutorial to install SnapML correctly:
+    # https://github.com/benchopt/benchmark_ridge/blob/tutorials/snapml_macos.rst
+    if 'snapml' in solver_class.name.lower() and sys.platform == 'darwin':
+        pytest.xfail('snapML is not easy to install on MacOS.')

tutorials/snapml_macos.rst

@@ -0,0 +1,58 @@
+============================
+Installing SnapML on macOS
+============================
+
+This tutorial provides step-by-step instructions to install SnapML on a macOS machine. The process includes setting up Homebrew and installing the necessary dependencies.
+
+Steps to Install SnapML
+========================
+
+1. **Install and Setup Homebrew**
+
+   Homebrew is a package manager for macOS that simplifies the installation of software.
+
+   Open your terminal and run the following command to install Homebrew:
+
+   .. code-block:: bash
+
+      arch -x86_64 /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+
+   After installing Homebrew, you need to add it to your shell environment:
+
+   .. code-block:: bash
+
+      echo 'eval "$(/usr/local/bin/brew shellenv)"' >> $HOME/.profile
+      eval "$(/usr/local/bin/brew shellenv)"
+
+2. **Install libomp**
+
+   `libomp` is an OpenMP library required by SnapML. Install it using Homebrew:
+
+   .. code-block:: bash
+
+      arch -x86_64 /usr/local/bin/brew install libomp
+
+   Once installed, set up the environment variables needed for `libomp`:
+
+   .. code-block:: bash
+
+      echo 'export LDFLAGS="-L/opt/homebrew/opt/libomp/lib"' >> $HOME/.profile
+      echo 'export CPPFLAGS="-I/opt/homebrew/opt/libomp/include"' >> $HOME/.profile
+      echo 'export DYLD_LIBRARY_PATH=$DYLD_LIBRARY_PATH:/opt/homebrew/opt/libomp/lib' >> $HOME/.profile
+
+   Apply the changes by running:
+
+   .. code-block:: bash
+
+      source $HOME/.profile
+
+3. **Install SnapML**
+
+   With the dependencies installed, you can now proceed to install SnapML using pip:
+
+   .. code-block:: bash
+
+      pip install snapml
+
+
+By following these steps, you should have SnapML installed and running correctly on your macOS machine.