From cdddf87c21e1614dc2b6fd2a25fd92decdea0950 Mon Sep 17 00:00:00 2001
From: kushalkolar <kushalkolar@gmail.com>
Date: Mon, 14 Oct 2024 04:20:35 -0400
Subject: [PATCH 1/3] add cov matrix example

---
 examples/machine_learning/covariance.py | 94 +++++++++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 examples/machine_learning/covariance.py

diff --git a/examples/machine_learning/covariance.py b/examples/machine_learning/covariance.py
new file mode 100644
index 000000000..111a7bd22
--- /dev/null
+++ b/examples/machine_learning/covariance.py
@@ -0,0 +1,94 @@
+"""
+Explore Covariance Matrix
+=========================
+
+Example showing how you can explore a covariance matrix with a selector tool.
+"""
+
+# test_example = false
+# sphinx_gallery_pygfx_docs = 'animate 10s'
+
+
+import fastplotlib as fpl
+from sklearn import datasets
+from sklearn.preprocessing import StandardScaler
+
+# load faces dataset
+faces = datasets.fetch_olivetti_faces()
+data = faces["data"]
+
+# sort the data so it's easier to understand the covariance matrix
+targets = faces["target"]
+sort_indices = targets.argsort()
+targets_sorted = targets[sort_indices]
+
+X = data[sort_indices]
+
+# scale the data w.r.t. mean and standard deviation
+X = StandardScaler().fit_transform(X)
+
+# compute covariance matrix
+X = X.T
+cov = X @ X.T / X.shape[1]
+
+# reshaped image for each sample wil be 64 x 64 pixels
+img = cov[0].reshape(64, 64)
+
+# figure kwargs for image widget
+# controller_ids = [[0, 1]] so we get independent controllers for each supblot
+# the covariance matrix is 4096 x 4096 and the reshaped image ix 64 x 64
+figure_kwargs = {"size": (700, 400), "controller_ids": [[0, 1]]}
+
+# create image widget
+iw = fpl.ImageWidget(
+    data=[cov, img],  # display the covariance matrix and reshaped image of a row
+    cmap="bwr",  # diverging colormap
+    names=["covariance", "row image"],
+    figure_kwargs=figure_kwargs,
+)
+
+# graphic that corresponds to image widget data array 0
+# 0 is the covariance matrix, 1 is the reshaped image of a row from the covariance matrix
+
+# add a linear selector to select y axis values so we can select rows of the cov matrix
+selector_cov = iw.managed_graphics[0].add_linear_selector(axis="y")
+
+# if you are exploring other types of matrices which are not-symmetric
+# you can also add a column selector by setting axis="x"
+
+# set vmin vmax
+for g in iw.managed_graphics:
+    g.vmin, g.vmax = -1, 1
+
+
+# event handler when the covariance matrix row changes
+@selector_cov.add_event_handler("selection")
+def update_img(ev):
+    # get the row index
+    ix = ev.get_selected_index()
+
+    # get the image the corresponds to this row
+    img = cov[ix].reshape(64, 64)
+
+    # change the reshaped image graphic data
+    iw.managed_graphics[1].data = img
+
+
+figure = iw.figure  # not required, just for the docs gallery to pick it up
+
+
+# move the selector programmatically, this is mainly for the docs gallery
+# for real use you can interact with the selector with your mouse
+def animate():
+    selector_cov.selection += 1
+
+
+iw.figure.add_animations(animate)
+
+iw.show()
+
+# NOTE: `if __name__ == "__main__"` is NOT how to use fastplotlib interactively
+# please see our docs for using fastplotlib interactively in ipython and jupyter
+if __name__ == "__main__":
+    print(__doc__)
+    fpl.run()

From 8ddfca80274060d5f631f345090666a53ed6fb8c Mon Sep 17 00:00:00 2001
From: kushalkolar <kushalkolar@gmail.com>
Date: Mon, 14 Oct 2024 04:21:55 -0400
Subject: [PATCH 2/3] 	new file:   examples/machine_learning/README.rst

---
 examples/machine_learning/README.rst | 2 ++
 1 file changed, 2 insertions(+)
 create mode 100644 examples/machine_learning/README.rst

diff --git a/examples/machine_learning/README.rst b/examples/machine_learning/README.rst
new file mode 100644
index 000000000..f6830887e
--- /dev/null
+++ b/examples/machine_learning/README.rst
@@ -0,0 +1,2 @@
+Machine Learning Examples
+=========================

From d3ad5766051fab40032acb464b0fb58077fd9841 Mon Sep 17 00:00:00 2001
From: kushalkolar <kushalkolar@gmail.com>
Date: Wed, 16 Oct 2024 23:38:46 -0400
Subject: [PATCH 3/3] update conf.py with machine_learning examples section

---
 docs/source/conf.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/docs/source/conf.py b/docs/source/conf.py
index 36d965b83..f65713270 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -56,15 +56,16 @@
     "subsection_order": ExplicitOrder(
         [
             "../../examples/image",
+            "../../examples/heatmap",
             "../../examples/image_widget",
             "../../examples/gridplot",
             "../../examples/line",
             "../../examples/line_collection",
             "../../examples/scatter",
-            "../../examples/heatmap",
-            "../../examples/misc",
             "../../examples/selection_tools",
+            "../../examples/machine_learning",
             "../../examples/guis",
+            "../../examples/misc",
             "../../examples/qt",
         ]
     ),