Added warnings when trying to compute local error with analytic exact (#339)

solution

Co-authored-by: Thomas Baumann <t.baumann@fz-juelich.de>

pySDC/implementations/problem_classes/AdvectionEquation_ND_FD.py

@@ -97,6 +97,11 @@ class advectionNd(GenericNDimFinDiff):
         sol : dtype_u
             The exact solution.
         """
+        if 'u_init' in kwargs.keys() or 't_init' in kwargs.keys():
+            self.logger.warn(
+                f'{type(self).__name__} uses an analytic exact solution from t=0. If you try to compute the local error, you will get the global error instead!'
+            )
+
         # Initialize pointers and variables
         ndim, freq, c, sigma, sol = self.ndim, self.freq, self.c, self.sigma, self.u_init
 

pySDC/implementations/problem_classes/HeatEquation_ND_FD.py

@@ -38,6 +38,11 @@ class heatNd_unforced(GenericNDimFinDiff):
         sol : dtype_u
             The exact solution.
         """
+        if 'u_init' in kwargs.keys() or 't_init' in kwargs.keys():
+            self.logger.warn(
+                f'{type(self).__name__} uses an analytic exact solution from t=0. If you try to compute the local error, you will get the global error instead!'
+            )
+
         ndim, freq, nu, sigma, dx, sol = self.ndim, self.freq, self.nu, self.sigma, self.dx, self.u_init
 
         if ndim == 1:

pySDC/implementations/problem_classes/NonlinearSchroedinger_MPIFFT.py

@@ -161,6 +161,10 @@ class nonlinearschroedinger_imex(ptype):
         u : dtype_u
             The exact solution.
         """
+        if 'u_init' in kwargs.keys() or 't_init' in kwargs.keys():
+            self.logger.warn(
+                f'{type(self).__name__} uses an analytic exact solution from t=0. If you try to compute the local error, you will get the global error instead!'
+            )
 
         def nls_exact_1D(t, x, c):
             ae = 1.0 / np.sqrt(2.0) * np.exp(1j * t)