[Dune] suggestion for example adaptivefinitevolume.cc

[Matteo Semplice]

Hi.
I was examining the source code of adaptivefinitevolume.cc in 
dune-grid-howto (version 2.1) and noticed that

1) the initial data is written to disk, the appropriate entry is 
inserted in concentration.series, but then the next call to vtkout opens 
concentration.series in write mode, erasing the entry about the first 
timestep. So I did:

--- adaptivefinitevolume.cc~    2011-04-29 17:31:53.000000000 +0200
+++ adaptivefinitevolume.cc     2011-11-26 16:55:57.000000000 +0100
@@ -42,7 +42,7 @@
    double dt, t=0;
    double saveStep = 0.1;
    const double saveInterval = 0.1;
-  int counter = 0;
+  int counter = 1; //file number 0 is the initial datum
    int k = 0;

    std::cout << "s=" << grid.size(0) << " k=" << k << " t=" << t << 
std::endl;

2) a minor point is that I think that saveStep should be computed from 
initial time and saveInterval, as follows

--- adaptivefinitevolume.cc~    2011-04-29 17:31:53.000000000 +0200
+++ adaptivefinitevolume.cc     2011-11-26 16:56:32.000000000 +0100
@@ -40,9 +40,9 @@

    // variables for time, timestep etc.
    double dt, t=0;
-  double saveStep = 0.1;
    const double saveInterval = 0.1;
-  int counter = 0;
+  double saveStep = t+saveInterval;
+  int counter = 1; //file number 0 is the initial datum
    int k = 0;

    std::cout << "s=" << grid.size(0) << " k=" << k << " t=" << t << 
std::endl;


     Matteo

-- 
Matteo Semplice				Dip. di Fisica e Matematica
Phone: 031-2386132			Università dell'Insubria
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