Add some information(paper ref, ...)

Author: AntSimi

README.md

@@ -1,5 +1,17 @@
 # README #
 
+### Method ###
+
+Method was described in :
+
+[Mason, E., A. Pascual, and J. C. McWilliams, 2014: A new sea surface height–based code for oceanic mesoscale eddy tracking.](https://doi.org/10.1002/2016JC012611)
+
+### Use case ###
+
+Method is used in :
+ 
+[Mason, E., A. Pascual, P. Gaube, S.Ruiz, J. Pelegrí, A. Delepoulle, 2017: Subregional characterization of mesoscale eddies across the Brazil-Malvinas Confluence](https://doi.org/10.1002/2016JC012611)
+
 ### How do I get set up? ###
 
 To avoid problems with installation, use of the virtualenv Python virtual environment is recommended.
@@ -33,7 +45,3 @@ EddyTracking tracking.yaml
 for tracking.
 
 
-# Py Eddy Tracker module #
-
-### Grid manipulation ###
-

src/py_eddy_tracker/eddy_feature.py

@@ -174,6 +174,7 @@ def detect_local_minima_(grid, general_mask, pixel_mask, maximum_local_extremum,
                     else:
                         g[i_ + 1, j_ + 1] = grid[i_ + i, j_ + j] * sign
             # if center equal to min
+            # TODO if center and neigboor have same value we have problem, i don't know how
             if g.min() == (grid[i, j] * sign) and pixel_mask[i,j]:
                 xs.append(i)
                 ys.append(j)
@@ -383,9 +384,12 @@ def __init__(self, x, y, z, levels, wrap_x=False, keep_unclose=False):
                     else:
                         closed_contours += 1
                     contour.vertices[-1] = contour.vertices[0]
-                # Store to use latter
                 x_min, y_min = contour.vertices.min(axis=0)
                 x_max, y_max = contour.vertices.max(axis=0)
+                ptp_min = self.DELTA_PREC * 100
+                if abs(x_min - x_max) < ptp_min or abs(y_min - y_max) < ptp_min:
+                    continue
+                # Store to use latter
                 contour.xmin = x_min
                 contour.xmax = x_max
                 contour.ymin = y_min