Remove argument `i_slice` of `select_ishapes`

Return `i_slice` instead. Since `i_slice` is now computed inside
`select_ishapes`.

Inst_eddies/Analysis/anim_eddy_contours.py

@@ -63,18 +63,14 @@ def anim_eddies(fig, ax, SHPC, window, d_min, d_max, light):
     ishape_lists_all = {}
     i_slices = {}
 
-    for d in range(d_min, d_max + 1):
-        i_slices[d] = SHPC.get_slice(d)
-
     for orientation in ["Anticyclones", "Cyclones"]:
         ishape_lists_all[orientation] = {}
 
         for d in range(d_min, d_max + 1):
-            ishape_lists_all[orientation][
-                d
-            ] = plot_eddy_contours.select_ishapes(
-                d, SHPC, i_slices[d], orientation, window
-            )
+            (
+                i_slices[d],
+                ishape_lists_all[orientation][d],
+            ) = plot_eddy_contours.select_ishapes(d, SHPC, orientation, window)
 
     if window is None:
         bbox = None

Inst_eddies/Analysis/plot_eddy_contours.py

@@ -25,16 +25,9 @@ import util_eddies
 
 
 def select_ishapes(
-    d: int,
-    SHPC: util_eddies.SHPC_class,
-    i_slice: int,
-    orientation: str,
-    window: list = None,
+    d: int, SHPC: util_eddies.SHPC_class, orientation: str, window: list = None
 ):
-    """Select ishapes at date d and in window. We assume date d is in
-    slice i_slice of the SHPC.
-
-    """
+    """Select ishapes at date d and in window."""
 
     i_slice, ishape_list = SHPC.ishape_range(d, orientation)
 
@@ -49,7 +42,7 @@ def select_ishapes(
             if util_eddies.in_window(points, window):
                 ishape_list_filt.append(ishape)
 
-    return ishape_list_filt
+    return i_slice, ishape_list_filt
 
 
 def snapshot(
@@ -259,14 +252,12 @@ if __name__ == "__main__":
     if args.date is None:
         d = SHPC.d_init[0]
         print("No date option, plotting first date of first slice:", d)
-        i_slice = 0
     else:
         d = args.date
-        i_slice = SHPC.get_slice(d)
 
     for orientation in ["Anticyclones", "Cyclones"]:
-        ishape_list = select_ishapes(
-            d, SHPC, i_slice, orientation=orientation, window=args.window
+        i_slice, ishape_list = select_ishapes(
+            d, SHPC, orientation=orientation, window=args.window
         )
         if len(ishape_list) == 0:
             print(f"{orientation}: No eddy found")