add helper for installing sklearn (#11)

* add helper for installing sklearn

* pseudo test

* patch bump

* explicitly return nothing

* optional verbosity

Co-authored-by: Alex Arslan <alex.arslan@beacon.bio>

Project.toml

@@ -1,7 +1,7 @@
 name = "PyMNE"
 uuid = "6c5003b2-cbe8-491c-a0d1-70088e6a0fd6"
 authors = ["Beacon Biosignals, Inc."]
-version = "0.1.1"
+version = "0.1.2"
 
 [deps]
 PyCall = "438e738f-606a-5dbb-bf0a-cddfbfd45ab0"
@@ -15,4 +15,4 @@ PyCall = "438e738f-606a-5dbb-bf0a-cddfbfd45ab0"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test =  ["PyCall", "Test"]
+test = ["PyCall", "Test"]

README.md

@@ -27,6 +27,8 @@ be changed via the `ENV["MNEVERSION"] = version_number` for your preferred
 the rather rapid API changes and deprecation cycle in MNE and as such, it is
 incumbent upon the user to manage these versions accordingly.
 
+Note that MNE-Python uses [scikit-learn](https://scikit-learn.org/stable/) for certain functionality (e.g. ICA and the `decoding` module), but does not install it automatically as a dependency.
+If you wish to take advantage of this functionality, the non-exported `install_sklearn` function will install `sklearn`, using the same environment variables as the main installation.
 
 MNE-Python can also be installed them manually ahead of time.
 From the shell, use `python -m pip install mne` for the latest stable release

src/PyMNE.jl

@@ -41,4 +41,25 @@ function __init__()
     return nothing
 end
 
+"""
+    install_sklearn(ver="")
+
+Install scikit-learn using the specified version.
+
+The default version is the latest stable version.
+"""
+function install_sklearn(version="latest"; verbose=false)
+    verbose && @info "Installing scikit-learn"
+    pip = pyimport("pip")
+    flags = split(get(ENV, "PIPFLAGS", ""))
+    packages = ["scikit-learn" * (version == "latest" ? "" : "==$version")]
+    if verbose
+        @info "Package requirements:" packages
+        @info "Flags for pip install:" flags
+        @info "scikit-learn version:" version
+    end
+    pip.main(["install"; flags; packages])
+    return nothing
+end
+
 end # module

test/runtests.jl

@@ -4,6 +4,12 @@ using Test
 
 using PyCall: PyError
 
+@testset "sklearn" begin
+    PyMNE.install_sklearn()
+    # requires sklearn
+    @test PyMNE.preprocessing.ICA(method="fastica") isa PyObject
+end
+
 @testset "create_info and get_info" begin
     dat = zeros(1, 100)
     naive_info = PyMNE.mne.create_info([:a], 100)