Changeset 2507 in lmdz_wrf for trunk

Timestamp:

May 4, 2019, 5:03:44 PM (6 years ago)

Author:

lfita

Message:

Adding:

• `join_circ_sec_rand': Function to join aa series of points by circular segments with random perturbations

Modifying `join_circ_sec' with a more generic formulation

File:

• trunk/tools/geometry_tools.py (modified) (3 diffs)

trunk/tools/geometry_tools.py

@@ -24 +24 @@
 # dist_points: Function to provide the distance between two points
 # join_circ_sec: Function to join aa series of points by circular segments
+# join_circ_sec_rand: Function to join aa series of points by circular segments with 
+#   random perturbations
 # max_coords_poly: Function to provide the extremes of the coordinates of a polygon
 # mirror_polygon: Function to reflex a polygon for a given axis
@@ -305 +307 @@
     Np = int(N/(Npts+1))
     for ip in range(Npts-1):
-        dps = dist_points(lpoints[ip], lpoints[ip+1])
-        jcirc_sec[Np*ip:Np*(ip+1),:] = circ_sec(lpoints[ip], lpoints[ip+1],          \
-          dps*radfrac, Np)
+        p1 = lpoints[ip]
+        p2 = lpoints[ip+1]
+        dps = dist_points(p1, p2)
+        jcirc_sec[Np*ip:Np*(ip+1),:] = circ_sec(p1, p2, dps*radfrac, Np)
 
     Np2 = N - (Npts-1)*Np
-    dps = dist_points(lpoints[Npts-1], lpoints[0])
-    jcirc_sec[(Npts-1)*Np:N,:] = circ_sec(lpoints[Npts-1], lpoints[0], dps*3., Np2)
+    p1 = lpoints[Npts-1]
+    p2 = lpoints[0]
+    dps = dist_points(p1, p2)
+    jcirc_sec[(Npts-1)*Np:N,:] = circ_sec(p1, p2, dps*3., Np2)
 
     return jcirc_sec
+
+def join_circ_sec_rand(points, radfrac=3., Lrand=0.1, N=200):
+    """ Function to join aa series of points by circular segments with random 
+        perturbations
+      points: main points of the island (clockwise ordered, to be joined by circular 
+        segments of radii as the radfrac factor of the distance between 
+        consecutive points)
+      radfrac: multiplicative factor of the distance between consecutive points to 
+        draw the circular segment (3., default)
+      Lrand: maximum length of the random perturbation to be added perpendicularly to 
+        the direction of the union line between points (0.1, default)
+      N: number of points (200, default)
+    """
+    import random
+    fname = 'join_circ_sec_rand'
+
+    jcirc_sec = np.ones((N,2), dtype=np.float)
+
+    # main points
+    lpoints = list(points)
+    Npts = len(lpoints)
+    Np = int(N/(Npts+1))
+    for ip in range(Npts-1):
+        p1 = lpoints[ip]
+        p2 = lpoints[ip+1]
+        dps = dist_points(p1, p2)
+        angle = np.arctan2(p2[0]-p1[0], p2[1]-p1[1]) + np.pi/2.
+        jcirc_sec[Np*ip:Np*(ip+1),:] = circ_sec(p1, p2, dps*radfrac, Np)
+        drand = Lrand*np.array([np.sin(angle), np.cos(angle)])
+        for iip in range(Np*ip,Np*(ip+1)):
+            jcirc_sec[iip,:] = jcirc_sec[iip,:] + drand*random.uniform(-1.,1.)
+
+    Np2 = N - (Npts-1)*Np
+    p1 = lpoints[Npts-1]
+    p2 = lpoints[0]
+    dps = dist_points(p1, p2)
+    angle = np.arctan2(p2[0]-p1[0], p2[1]-p1[1]) + np.pi/2.
+    jcirc_sec[(Npts-1)*Np:N,:] = circ_sec(p1, p2, dps*3., Np2)
+    drand = Lrand*np.array([np.sin(angle), np.cos(angle)])
+    for iip in range(Np*(Npts-1),N):
+        jcirc_sec[iip,:] = jcirc_sec[iip,:] + drand*random.uniform(-1.,1.)
+
+    return jcirc_sec
+
 
 ####### ###### ##### #### ### ## #
@@ -938 +987 @@
 
     # Coastline
-   
-    island1 = join_circ_sec(mainpts, radfrac=3., N=200)
+    island1 = join_circ_sec_rand(mainpts)
 
     islandsecs = ['coastline']