Implement `control_samples` function as is in GN1

Issue:
https://github.com/genenetwork/gn-gemtext-threads/blob/main/topics/gn1-migration-to-gn2/partial-correlations.gmi

* gn3/partial_correlations.py: Implement `control_samples` function
* tests/unit/test_partial_correlations.py: add tests for `control_samples`
  function

  Implement the function `control_samples` and make it mostly bug-compatible
  with the `web/webqtl/correlation/correlationFunction.controlStrain` function
  in GN1.

  This implementation in GN3 does not do any calls to the database. It will
  rely on other functions to provide the data from the database to it.

1 files changed, 80 insertions, 0 deletions

diff --git a/tests/unit/test_partial_correlations.py b/tests/unit/test_partial_correlations.py
index f204d4f..0083ef7 100644
--- a/tests/unit/test_partial_correlations.py
+++ b/tests/unit/test_partial_correlations.py
@@ -1,7 +1,87 @@
 """Module contains tests for gn3.partial_correlations"""
 
 from unittest import TestCase
+from gn3.partial_correlations import control_samples
 
+sampleslist = ["B6cC3-1", "BXD1", "BXD12", "BXD16", "BXD19", "BXD2"]
+control_traits = (
+    {
+        "mysqlid": 36688172,
+        "data": {
+            "B6cC3-1": {
+                "sample_name": "B6cC3-1", "value": 7.51879, "variance": None,
+                "ndata": None},
+            "BXD1": {
+                "sample_name": "BXD1", "value": 7.77141, "variance": None,
+                "ndata": None},
+            "BXD12": {
+                "sample_name": "BXD12", "value": 8.39265, "variance": None,
+                "ndata": None},
+            "BXD16": {
+                "sample_name": "BXD16", "value": 8.17443, "variance": None,
+                "ndata": None},
+            "BXD19": {
+                "sample_name": "BXD19", "value": 8.30401, "variance": None,
+                "ndata": None},
+            "BXD2": {
+                "sample_name": "BXD2", "value": 7.80944, "variance": None,
+                "ndata": None}}},
+    {
+        "mysqlid": 36688172,
+        "data": {
+            "B6cC3-21": {
+                "sample_name": "B6cC3-1", "value": 7.51879, "variance": None,
+                "ndata": None},
+            "BXD21": {
+                "sample_name": "BXD1", "value": 7.77141, "variance": None,
+                "ndata": None},
+            "BXD12": {
+                "sample_name": "BXD12", "value": 8.39265, "variance": None,
+                "ndata": None},
+            "BXD16": {
+                "sample_name": "BXD16", "value": 8.17443, "variance": None,
+                "ndata": None},
+            "BXD19": {
+                "sample_name": "BXD19", "value": 8.30401, "variance": None,
+                "ndata": None},
+            "BXD2": {
+                "sample_name": "BXD2", "value": 7.80944, "variance": None,
+                "ndata": None}}},
+    {
+        "mysqlid": 36688172,
+        "data": {
+            "B6cC3-1": {
+                "sample_name": "B6cC3-1", "value": 7.51879, "variance": None,
+                "ndata": None},
+            "BXD1": {
+                "sample_name": "BXD1", "value": 7.77141, "variance": None,
+                "ndata": None},
+            "BXD12": {
+                "sample_name": "BXD12", "value": None, "variance": None,
+                "ndata": None},
+            "BXD16": {
+                "sample_name": "BXD16", "value": None, "variance": None,
+                "ndata": None},
+            "BXD19": {
+                "sample_name": "BXD19", "value": None, "variance": None,
+                "ndata": None},
+            "BXD2": {
+                "sample_name": "BXD2", "value": 7.80944, "variance": None,
+                "ndata": None}}})
 
 class TestPartialCorrelations(TestCase):
     """Class for testing partial correlations computation functions"""
+
+    def test_control_samples(self):
+        """Test that the control_samples works as expected."""
+        self.assertEqual(
+            control_samples(control_traits, sampleslist),
+            ((("B6cC3-1", "BXD1", "BXD12", "BXD16", "BXD19", "BXD2"),
+              ("BXD12", "BXD16", "BXD19", "BXD2"),
+              ("B6cC3-1", "BXD1", "BXD2")),
+             ((7.51879, 7.77141, 8.39265, 8.17443, 8.30401, 7.80944),
+              (8.39265, 8.17443, 8.30401, 7.80944),
+              (7.51879, 7.77141, 7.80944)),
+             ((None, None, None, None, None, None), (None, None, None, None),
+              (None, None, None)),
+             (6, 4, 3)))