Update utils.py

With the change, the function shouldn't get into trouble if it created a BSpline with a degree >3

partitioned-heat-conduction/fenics/utils/utils.py

@@ -13,7 +13,7 @@ def b_splines(precice, degree, dt):
     '''
     # use equidistant samples
     # apparently you need 2k+2 samples for degree k
-    nodes = np.linspace(0,dt,2*3+3)  # <-- But these are 2k+3 samples
+    nodes = np.linspace(0,dt,2*degree+3)  # <-- But these are 2k+3 samples
     weights = []
     b_splines = {}
 
@@ -26,4 +26,4 @@ def b_splines(precice, degree, dt):
             weights_k.append(weights[i][k])
         b1,b2,b3 = interpol.splrep(nodes, weights_k,s=0, k=degree)
         b_splines[k] = interpol.BSpline(b1, b2, b3, extrapolate=False)
-    return b_splines
+    return b_splines