DOC/TEST: Update report tutorial and tests for rank parameter

Author: AasmaGupta

mne/report/tests/test_report.py

@@ -1360,3 +1360,17 @@ def test_gif(tmp_path):
     bad_name.write_bytes(b"")
     with pytest.raises(ValueError, match="Allowed values"):
         r.add_image(bad_name, "fname")
+
+def test_add_covariance_rank():
+    from mne import create_info
+    from mne.cov import make_ad_hoc_cov
+    from mne.report import Report
+
+    info = create_info(ch_names=["EEG 001"], sfreq=1000, ch_types=["eeg"])
+    cov = make_ad_hoc_cov(info)
+
+    report = Report()
+    report.add_covariance(cov, info=info, title="Test Cov", rank=1)
+
+    html = "".join(report.html)
+    assert "Rank" in html

tutorials/intro/70_report.py

@@ -164,7 +164,16 @@
 cov_path = sample_dir / "sample_audvis-cov.fif"
 
 report = mne.Report(title="Covariance example")
-report.add_covariance(cov=cov_path, info=raw_path, title="Covariance")
+
+# Optionally display the covariance rank in the report
+rank = 60
+
+report.add_covariance(
+    cov,
+    info=info,
+    title="Noise covariance",
+    rank=rank,
+)
 report.save("report_cov.html", overwrite=True)
 
 # %%