int RealTier_interpolateQuadratically (I, long numberOfPointsPerParabola, int logarithmically) {
iam (RealTier);
RealTier thee = (structRealTier *)Data_copy (me); cherror
for (long ipoint = 1; ipoint < my points -> size; ipoint ++) {
RealPoint point1 = (structRealPoint *)my points -> item [ipoint], point2 = (structRealPoint *)my points -> item [ipoint + 1];
double time1 = point1 -> time, time2 = point2 -> time, tmid = 0.5 * (time1 + time2);
double value1 = point1 -> value, value2 = point2 -> value, valuemid;
double timeStep = (tmid - time1) / (numberOfPointsPerParabola + 1);
if (logarithmically) value1 = log (value1), value2 = log (value2);
valuemid = 0.5 * (value1 + value2);
/*
* Left from the midpoint.
*/
for (long inewpoint = 1; inewpoint <= numberOfPointsPerParabola; inewpoint ++) {
double newTime = time1 + inewpoint * timeStep;
double phase = (newTime - time1) / (tmid - time1);
double newValue = value1 + (valuemid - value1) * phase * phase;
if (logarithmically) newValue = exp (newValue);
RealTier_addPoint (thee, newTime, newValue); cherror
}
/*
* The midpoint.
*/
RealTier_addPoint (thee, tmid, logarithmically ? exp (valuemid) : valuemid); cherror
/*
* Right from the midpoint.
*/
for (long inewpoint = 1; inewpoint <= numberOfPointsPerParabola; inewpoint ++) {
double newTime = tmid + inewpoint * timeStep;
double phase = (time2 - newTime) / (time2 - tmid);
double newValue = value2 + (valuemid - value2) * phase * phase;
if (logarithmically) newValue = exp (newValue);
RealTier_addPoint (thee, newTime, newValue); cherror
}
}
end:
iferror { forget (thee); return 0; }
Thing_swap (me, thee);
forget (thee);
return 1;
}
void RealTier_interpolateQuadratically (RealTier me, long numberOfPointsPerParabola, int logarithmically) {
try {
autoRealTier thee = Data_copy (me);
for (long ipoint = 1; ipoint < my points.size; ipoint ++) {
RealPoint point1 = my points.at [ipoint], point2 = my points.at [ipoint + 1];
double time1 = point1 -> number, time2 = point2 -> number, tmid = 0.5 * (time1 + time2);
double value1 = point1 -> value, value2 = point2 -> value, valuemid;
double timeStep = (tmid - time1) / (numberOfPointsPerParabola + 1);
if (logarithmically) value1 = log (value1), value2 = log (value2);
valuemid = 0.5 * (value1 + value2);
/*
* Left from the midpoint.
*/
for (long inewpoint = 1; inewpoint <= numberOfPointsPerParabola; inewpoint ++) {
double newTime = time1 + inewpoint * timeStep;
double phase = (newTime - time1) / (tmid - time1);
double newValue = value1 + (valuemid - value1) * phase * phase;
if (logarithmically) newValue = exp (newValue);
RealTier_addPoint (thee.get(), newTime, newValue);
}
/*
* The midpoint.
*/
RealTier_addPoint (thee.get(), tmid, logarithmically ? exp (valuemid) : valuemid);
/*
* Right from the midpoint.
*/
for (long inewpoint = 1; inewpoint <= numberOfPointsPerParabola; inewpoint ++) {
double newTime = tmid + inewpoint * timeStep;
double phase = (time2 - newTime) / (time2 - tmid);
double newValue = value2 + (valuemid - value2) * phase * phase;
if (logarithmically) newValue = exp (newValue);
RealTier_addPoint (thee.get(), newTime, newValue);
}
}
Thing_swap (me, thee.get());
} catch (MelderError) {
Melder_throw (me, U": not interpolated quadratically.");
}
}
