examples: minor fix + readme

example/maxwell_linear/Makefile

-BIN=../bin
+BIN=../../bin
 
 test:
 	@echo "make cim: run the countour integral solver"

example/maxwell_linear/README.txt

+This is a simple linear eigenvalue problem example. It consists in a rectangular
+electromagnetic cavity. Simply run:
+  make cim
+to test cim.py.
+The Makefile will first mesh the geometry square.geo by calling Gmsh.
+Afterwards, cim.py is called. The GetDP formulation is located in maxwell.pro.
+In the GetDP formulation, the variables:
+  angularFreqRe
+  angularFreqIm
+  x()
+  b()
+  imposeRHS
+  doPostpro
+  doApply
+  fileName
+are reserved for cim.py.
+
+In order to check the solution, simply run:
+  make ref
+This will solve the linear eigenvalue problem with a classical algorithm.
+This resolution is implemented in ref.pro. If you use GetDP with SLEPc,
+the default algorithm should be Krylov-Schur.

example/maxwell_linear/maxwell.pro

@@ -17,8 +17,7 @@ Function{
 
   // Algebraic data //
   DefineConstant[x() = {},  // Solution
-                 b() = {},  // Right hand side
-                 d() = {}]; // DoFs
+                 b() = {}]; // Right hand side
 
   // Control data //
   DefineConstant[imposeRHS = 0,          // Should I use an imposed RHS?

example/maxwell_sibc/Makefile

+BIN=../../bin
+
 sphere: init cim
 
 init:
 	gmsh sphere.geo -3
 
 cim:
-	cim.py sphere.pro sphere.msh Solve Post 5.48e12+4.23e05j 1e11 -nodes 10 -lStart 4
+	python ${BIN}/cim.py sphere.pro sphere.msh Solve Post 5.48e12+4.23e05j 1e11 -nodes 10 -lStart 4
 
 clean:
 	rm -f *.pos

example/maxwell_sibc/README.txt

+This is a non-linear eigenvalue problem example. It consists in a spherical
+electromagnetic cavity. The wall conductivity is modelled by a Leontovich
+surface impedance boundary condition (SIBC). Simply run:
+  make
+to test cim.py.
+The Makefile will first mesh the geometry square.geo by calling Gmsh.
+Afterwards, cim.py is called. The GetDP formulation is located in sphere.pro.
+In the GetDP formulation, the variables:
+  angularFreqRe
+  angularFreqIm
+  x()
+  b()
+  imposeRHS
+  doPostpro
+  doApply
+  fileName
+are reserved for cim.py. The parts of the GetDP code related to cim.py are
+located in cimParameters.pro and cimResolution.pro.
+
+For the default parameters:
+  radius = 150e-6 m
+  conductivity = 1e15 S/m
+the analytical resonance angular frequency for the fundamental mode should be:
+  5.48362e12+4.24068e05j
+where j is the imaginary unit. This analytical result comes from the reference:
+  S. Papantonis and S. Lucyszyn, "Lossy spherical cavity resonators for
+  stress-testing arbitrary 3D eigenmode solvers," Progress In Electromagnetics
+  Research, vol. 151, pp. 151-167, 2015.

example/maxwell_sibc/physics.pro

-/////////////////////////////
-// Some physical constants //
-/////////////////////////////