Print error if required package is missing or too old #260

Author: rlabbe

00-Preface.ipynb

@@ -722,7 +722,7 @@
     {
      "data": {
       "text/plain": [
-       "[<matplotlib.lines.Line2D at 0x24ec4f535c0>]"
+       "[<matplotlib.lines.Line2D at 0x1f04c819fc8>]"
       ]
      },
      "execution_count": 18,
@@ -974,7 +974,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.6.10"
+   "version": "3.7.6"
   },
   "nbdime-conflicts": {
    "local_diff": [

book_format.py

@@ -19,44 +19,95 @@
 from contextlib import contextmanager
 from IPython.core.display import HTML
 import json
-import matplotlib
-import matplotlib.pylab as pylab
-import matplotlib.pyplot as plt
-import numpy as np
 import os.path
 import sys
 import warnings
 from kf_book.book_plots import set_figsize, reset_figsize
 
-# version 1.4.3 of matplotlib has a bug that makes
-# it issue a spurious warning on every plot that
-# clutters the notebook output
-if matplotlib.__version__ == '1.4.3':
-    warnings.simplefilter(action="ignore", category=FutureWarning)
+def test_installation():
+    try:
+        import filterpy
+    except:
+        print("Please install FilterPy from the command line by running the command\n\t$ pip install filterpy\n\nSee chapter 0 for instructions.")
 
-try:
-    matplotlib.style.use('default')
-except:
-    pass
+    try:
+        import numpy
+    except:
+        print("Please install NumPy before continuing. See chapter 0 for instructions.")
 
-def test_filterpy_version():
+    try:
+        import scipy
+    except:
+        print("Please install SciPy before continuing. See chapter 0 for instructions.")
+
+    try:
+        import sympy
+    except:
+        print("Please install SymPy before continuing. See chapter 0 for instructions.")
+
+    try:
+        import matplotlib
+    except:
+        print("Please install matplotlib before continuing. See chapter 0 for instructions.")
 
-    import filterpy
     from distutils.version import LooseVersion
 
     v = filterpy.__version__
     min_version = "1.4.4"
     if LooseVersion(v) < LooseVersion(min_version):
-       raise Exception("Minimum FilterPy version supported is {}.\n"
-                       "Please install a more recent version.\n"
-                       "   ex: pip install filterpy --upgrade".format(
+       print("Minimum FilterPy version supported is {}. "
+             "Please install a more recent version.\n"
+             "   ex: pip install filterpy --upgrade".format(
              min_version))
 
 
-# ensure that we have the correct filterpy loaded. This is
+    v = matplotlib.__version__
+    min_version = "1.5.0" # this is really old!!!
+    if LooseVersion(v) < LooseVersion(min_version):
+       print("Minimum Matplotlib version supported is {}. "
+             "Please install a more recent version.".format(min_version))
+
+    # require Python 2.7, or 3.5+
+
+    import sys
+    v = sys.version_info
+    if v.major > 3:
+        # I guess if we are this far in the future it'll work? Who knows.
+        # I just don't want to start getting issue reports when Python goes
+        # to 4.0
+        return
+
+    if (v.major == 2 and v.minor != 7) or (v.major == 3 and v.minor < 5):
+        print('You must use Python version 2.7 or 3.5+ for the notebooks to work correctly')
+
+
+    # need to add test for IPython. I think I want to be at 6, which also implies
+    # Python 3, matplotlib 2+, etc.
+
+# ensure that we have the correct packages loaded. This is
 # called when this module is imported at the top of each book
-# chapter so the reader can see that they need to update FilterPy.
-test_filterpy_version()
+# chapter so the reader can see that they need to update their environment.
+test_installation()
+
+
+# now that we've tested the existence of all packages go ahead and import
+
+import matplotlib
+import matplotlib.pylab as pylab
+import matplotlib.pyplot as plt
+import numpy as np
+
+# version 1.4.3 of matplotlib has a bug that makes
+# it issue a spurious warning on every plot that
+# clutters the notebook output
+if matplotlib.__version__ == '1.4.3':
+    warnings.simplefilter(action="ignore", category=FutureWarning)
+
+try:
+    matplotlib.style.use('default')
+except:
+    pass
+
 
 with warnings.catch_warnings():
     warnings.simplefilter("ignore", matplotlib.MatplotlibDeprecationWarning)

requirements.txt

@@ -1,5 +1,4 @@
 filterpy
-seaborn
 jupyter
 notebook
 sympy