Left- and right-handed coordinate systems (#70)

* Add example for LHS/RHS coordinate system
* Bugfix related to `pts_per_dec` being floats and used as inputs to `logspace`/`linspace`.

.travis.yml

@@ -17,11 +17,11 @@ matrix:
     - python: 3.7  # => without matplotlib, numexpr
       env: PYTHON=3.7 CHAN="defaults" PCKGS="" TEST="" INST=""
     - python: 3.7  # => just linkcheck
-      env: PYTHON=3.7 CHAN="defaults" CHCKLNKS=true PCKGS="" TEST="" INST="sphinx numpydoc sphinx_rtd_theme sphinx_numfig sphinx_gallery"
+      env: PYTHON=3.7 CHAN="defaults" CHCKLNKS=true PCKGS="" TEST="" INST="sphinx numpydoc sphinx_rtd_theme sphinx_numfig sphinx_gallery memory_profiler"
 
 jobs:
   allow_failures:  # env must be EXACTLY as env allowed to fail.
-    - env: PYTHON=3.7 CHAN="defaults" CHCKLNKS=true PCKGS="" TEST="" INST="sphinx numpydoc sphinx_rtd_theme sphinx_numfig sphinx_gallery"
+    - env: PYTHON=3.7 CHAN="defaults" CHCKLNKS=true PCKGS="" TEST="" INST="sphinx numpydoc sphinx_rtd_theme sphinx_numfig sphinx_gallery memory_profiler"
 
 install:
   - sudo apt-get update

docs/conf.py

@@ -42,6 +42,12 @@
     "filename_pattern": r"\.py",
     # Sort gallery example by file name instead of number of lines (default)
     "within_subsection_order": FileNameSortKey,
+    # Remove the settings (e.g., sphinx_gallery_thumbnail_number)
+    'remove_config_comments': True,
+    # Show memory
+    'show_memory': True,
+    # Custom first notebook cell
+    'first_notebook_cell': '%matplotlib notebook',
 }
 
 # https://github.com/sphinx-gallery/sphinx-gallery/pull/521/files
@@ -52,7 +58,7 @@
 
 # Intersphinx configuration
 # intersphinx_mapping = {
-#     "numpy": ("https://docs.scipy.org/doc/numpy/", None),
+#     "numpy": ("https://numpy.org", None),
 #     "scipy": ("https://docs.scipy.org/doc/scipy/reference", None),
 # }
 

docs/manual.rst

@@ -206,6 +206,20 @@ calculation. It could also be used in the high-frequency range to model
 dielectricity.
 
 
+Coordinate system
+'''''''''''''''''
+
+The used coordinate system is either a
+
+- Left-Handed System (LHS), where Easting is the :math:`x`-direction, Northing
+  the :math:`y`-direction, and positive :math:`z` is pointing downwards;
+- Right-Handed System (RHS), where Easting is the :math:`x`-direction, Northing
+  the :math:`y`-direction, and positive :math:`z` is pointing upwards.
+
+Have a look at the example :ref:`sphx_glr_examples_coordinate_system.py` for
+further explanations.
+
+
 Contributing
 ------------
 

empymod/model.py

@@ -108,11 +108,11 @@ def bipole(src, rec, depth, res, freqtime, signal=None, aniso=None,
               different angles, you have to use the bipole-method (with
               srcpts/recpts = 1, so it is calculated as dipoles).
 
-        Angles (coordinate system is left-handed, positive z down
-        (East-North-Depth):
+        Angles (coordinate system is either left-handed with positive z down or
+        right-handed with positive z up; East-North-Depth):
 
             - azimuth (°): horizontal deviation from x-axis, anti-clockwise.
-            - dip (°): vertical deviation from xy-plane downwards.
+            - +/-dip (°): vertical deviation from xy-plane down/up-wards.
 
         Sources or receivers placed on a layer interface are considered in the
         upper layer.
@@ -1010,11 +1010,11 @@ def loop(src, rec, depth, res, freqtime, signal=None, aniso=None, epermH=None,
               recpts = 1, so it is calculated as dipoles). Note that srcpts is
               fixed to 1, as the source is a loop.
 
-        Angles (coordinate system is left-handed, positive z down
-        (East-North-Depth):
+        Angles (coordinate system is either left-handed with positive z down or
+        right-handed with positive z up; East-North-Depth):
 
             - azimuth (°): horizontal deviation from x-axis, anti-clockwise.
-            - dip (°): vertical deviation from xy-plane downwards.
+            - +/-dip (°): vertical deviation from xy-plane down/up-wards.
 
         Sources or receivers placed on a layer interface are considered in the
         upper layer.

empymod/scripts/fdesign.py

@@ -1315,7 +1315,7 @@ def _calculate_filter(n, spacing, shift, fI, r_def, reim, name):
     # r :: Start/end is defined by base AND r_def[0]/r_def[1]
     #      Overdetermined system if r_def[2] > 1
     r = np.logspace(np.log10(1/np.max(base)) - r_def[0],
-                    np.log10(1/np.min(base)) + r_def[1], r_def[2]*n)
+                    np.log10(1/np.min(base)) + r_def[1], int(r_def[2]*n))
 
     # k :: Get required k-values (matrix of shape (r.size, base.size))
     k = base/r[:, None]

empymod/transform.py

@@ -432,7 +432,7 @@ def hquad(zsrc, zrec, lsrc, lrec, off, factAng, depth, ab, etaH, etaV, zetaH,
     # Get required lambdas
     la = np.log10(a)
     lb = np.log10(b)
-    ilambd = np.logspace(la, lb, (lb-la)*pts_per_dec + 1)
+    ilambd = np.logspace(la, lb, int((lb-la)*pts_per_dec + 1))
 
     # Call the kernel
     PJ0, PJ1, PJ0b = kernel.wavenumber(zsrc, zrec, lsrc, lrec, depth, etaH,