Replace the usage of widget with ipympl.

The "widget" backend is an alias to the ipympl backend. The associated package
is ipympl. By using the ipympl backend in the ipython magic, the dependency on
the ipympl package is made explicit and clear to the user.

Author: zivy

Python/03_Image_Details.ipynb

@@ -1436,7 +1436,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%matplotlib widget\n",
+    "%matplotlib ipympl\n",
     "import gui\n",
     "\n",
     "gui.RegistrationPointDataAquisition(\n",

Python/04_Image_Display.ipynb

@@ -57,7 +57,7 @@
    "source": [
     "import SimpleITK as sitk\n",
     "\n",
-    "%matplotlib widget\n",
+    "%matplotlib ipympl\n",
     "import matplotlib.pyplot as plt\n",
     "import gui\n",
     "\n",

Python/05_Results_Visualization.ipynb

@@ -70,7 +70,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%matplotlib widget\n",
+    "%matplotlib ipympl\n",
     "\n",
     "import numpy as np\n",
     "import itertools\n",

Python/21_Transforms_and_Resampling.ipynb

@@ -774,7 +774,7 @@
    "outputs": [],
    "source": [
     "# Temporarily change the matplotlib back-end to enable mouse interaction\n",
-    "%matplotlib widget\n",
+    "%matplotlib ipympl\n",
     "intensity_profiles_image = sitk.ReadImage(fdata(\"training_001_ct.mha\"))\n",
     "point_gui = gui.PointDataAquisition(image=intensity_profiles_image);"
    ]

Python/30_Segmentation_Region_Growing.ipynb

@@ -60,9 +60,9 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "# To use interactive plots (mouse clicks, zooming, panning) we use the notebook back end. We want our graphs\n",
-    "# to be embedded in the notebook, inline mode, this combination is defined by the magic \"%matplotlib widget\".\n",
-    "%matplotlib widget\n",
+    "# To use interactive plots (mouse clicks, zooming, panning) we use the ipympl back end. We want our graphs\n",
+    "# to be embedded in the notebook, inline mode, this combination is defined by the magic \"%matplotlib ipympl\".\n",
+    "%matplotlib ipympl\n",
     "\n",
     "import SimpleITK as sitk\n",
     "\n",

Python/33_Segmentation_Thresholding_Edge_Detection.ipynb

@@ -67,7 +67,7 @@
     "%run update_path_to_download_script\n",
     "from downloaddata import fetch_data as fdata\n",
     "\n",
-    "%matplotlib widget\n",
+    "%matplotlib ipympl\n",
     "import gui\n",
     "import matplotlib.pyplot as plt\n",
     "\n",

Python/35_Segmentation_Shape_Analysis.ipynb

@@ -25,7 +25,7 @@
     "import SimpleITK as sitk\n",
     "import pandas as pd\n",
     "\n",
-    "%matplotlib widget\n",
+    "%matplotlib ipympl\n",
     "\n",
     "import matplotlib.pyplot as plt\n",
     "import gui\n",

Python/36_Microscopy_Colocalization_Distance_Analysis.ipynb

@@ -25,7 +25,7 @@
     "import numpy as np\n",
     "import pandas as pd\n",
     "\n",
-    "%matplotlib widget\n",
+    "%matplotlib ipympl\n",
     "import gui\n",
     "\n",
     "%run update_path_to_download_script\n",

Python/63_Registration_Initialization.ipynb

@@ -62,7 +62,7 @@
     "%run update_path_to_download_script\n",
     "from downloaddata import fetch_data as fdata\n",
     "\n",
-    "%matplotlib widget\n",
+    "%matplotlib ipympl\n",
     "import gui\n",
     "\n",
     "\n",

Python/67_Registration_Semiautomatic_Homework.ipynb

@@ -70,9 +70,9 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "# To use interactive plots (mouse clicks, zooming, panning) we use the notebook back end. We want our graphs\n",
-    "# to be embedded in the notebook, inline mode, this combination is defined by the magic \"%matplotlib widget\".\n",
-    "%matplotlib widget\n",
+    "# To use interactive plots (mouse clicks, zooming, panning) we use the ipympl back end. We want our graphs\n",
+    "# to be embedded in the notebook, inline mode, this combination is defined by the magic \"%matplotlib ipympl\".\n",
+    "%matplotlib ipympl\n",
     "\n",
     "import numpy as np\n",
     "import SimpleITK as sitk\n",