OilfieldToolsNet/opm-core
4
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

spline: fix the monotinic_() method and creation of monotonic splines

Browse Source 
also, extend the unit test for it. (*phew* that was much more fun than
appreciated because of all the index shifts. I'm still not 100% sure
that everything works in all corner cases, but at least my confidence
is at 95%.)
This commit is contained in:
Andreas Lauser
2013-11-07 19:53:31 +01:00
parent c9067c4bda
commit ae901534c3
2 changed files with 136 additions and 69 deletions
Download Patch File Download Diff File Expand all files Collapse all files
tests/test_spline.cpp
+50 -2
View File
@@ -175,6 +175,54 @@ void testNatural(const Spline &sp,
<< (d3 - d2)/eps << " ought to be 0");
}
template <class Spline>
void testMonotonic(const Spline &sp,
const double *x,
const double *y)
{
// test the common properties of splines
testCommon(sp, x, y);
int n = sp.numSamples();
for (int i = 0; i < n - 1; ++ i) {
// make sure that the spline is monotonic for each interval
// between sampling points
if (!sp.monotonic(x[i], x[i + 1]))
OPM_THROW(std::runtime_error,
"Spline says it is not monotonic in interval "
<< i << " where it should be");
// test the intersection methods
double d = (y[i] + y[i+1])/2;
double interX = sp.intersectInterval(x[i], x[i+1],
/*a=*/0, /*b=*/0, /*c=*/0, d);
double interY = sp.eval(interX);
if (std::abs(interY - d) > 1e-5)
OPM_THROW(std::runtime_error,
"Spline::intersectInterval() seems to be broken: "
<< sp.eval(interX) << " - " << d << " = " << sp.eval(interX) - d << "!");
}
// make sure the spline says to be monotonic on the (extrapolated)
// left and right sides
if (!sp.monotonic(x[0] - 1.0, (x[0] + x[1])/2, /*extrapolate=*/true))
OPM_THROW(std::runtime_error,
"Spline says it is not monotonic on left side where it should be");
if (!sp.monotonic((x[n - 2]+ x[n - 1])/2, x[n-1] + 1.0, /*extrapolate=*/true))
OPM_THROW(std::runtime_error,
"Spline says it is not monotonic on right side where it should be");
for (int i = 0; i < n - 2; ++ i) {
// make sure that the spline says that it is non-monotonic for
// if extrema are within the queried interval
if (sp.monotonic((x[i] + x[i + 1])/2, (x[i + 1] + x[i + 2])/2))
OPM_THROW(std::runtime_error,
"Spline says it is monotonic in interval "
<< i << " where it should not be");
}
}
void testAll()
{
double x[] = { 0, 5, 7.5, 8.75, 9.375 };
@@ -261,6 +309,8 @@ void plot()
Opm::Spline<double> spPeriodic(xs, ys, /*type=*/Opm::Spline<double>::Periodic);
Opm::Spline<double> spMonotonic(xs, ys, /*type=*/Opm::Spline<double>::Monotonic);
testMonotonic(spMonotonic, x_, y_);
spFull.printCSV(x_[0] - 1.00001,
x_[n] + 1.00001,
1000);
@@ -279,8 +329,6 @@ void plot()
x_[n] + 1.00001,
1000);
std::cout << "\n";
std::cerr << "Spline is monotonic: " << spFull.monotonic(x_[0], x_[n]) << "\n";
}
int main(int argc, char** argv)