void Vector_getMinimumAndX (Vector me, double xmin, double xmax, long channel, int interpolation,
double *return_minimum, double *return_xOfMinimum)
{
long imin, imax, n = my nx;
Melder_assert (channel >= 1 && channel <= my ny);
double *y = my z [channel];
double minimum, x;
if (xmax <= xmin) { xmin = my xmin; xmax = my xmax; }
if (! Sampled_getWindowSamples (me, xmin, xmax, & imin, & imax)) {
/*
* No samples between xmin and xmax.
* Try to return the lesser of the values at these two points.
*/
double yleft = Vector_getValueAtX (me, xmin, channel,
interpolation > Vector_VALUE_INTERPOLATION_NEAREST ? Vector_VALUE_INTERPOLATION_LINEAR : Vector_VALUE_INTERPOLATION_NEAREST);
double yright = Vector_getValueAtX (me, xmax, channel,
interpolation > Vector_VALUE_INTERPOLATION_NEAREST ? Vector_VALUE_INTERPOLATION_LINEAR : Vector_VALUE_INTERPOLATION_NEAREST);
minimum = yleft < yright ? yleft : yright;
x = yleft == yright ? (xmin + xmax) / 2 : yleft < yright ? xmin : xmax;
} else {
minimum = y [imin], x = imin;
if (y [imax] < minimum) minimum = y [imax], x = imax;
if (imin == 1) imin ++;
if (imax == my nx) imax --;
for (long i = imin; i <= imax; i ++) {
if (y [i] < y [i - 1] && y [i] <= y [i + 1]) {
double i_real, localMinimum = NUMimproveMinimum (y, n, i, interpolation, & i_real);
if (localMinimum < minimum) minimum = localMinimum, x = i_real;
}
}
x = my x1 + (x - 1) * my dx; /* Convert sample to x. */
if (x < xmin) x = xmin; else if (x > xmax) x = xmax;
}
if (return_minimum) *return_minimum = minimum;
if (return_xOfMinimum) *return_xOfMinimum = x;
}
void Sampled_getMinimumAndX (Sampled me, double xmin, double xmax, long ilevel, int unit, int interpolate,
double *return_minimum, double *return_xOfMinimum)
{
long imin, imax, i;
double minimum = 1e301, xOfMinimum = 0.0;
if (xmin == NUMundefined || xmax == NUMundefined) {
minimum = xOfMinimum = NUMundefined;
goto end;
}
Function_unidirectionalAutowindow (me, & xmin, & xmax);
if (! Function_intersectRangeWithDomain (me, & xmin, & xmax)) {
minimum = xOfMinimum = NUMundefined; // requested range and logical domain do not intersect
goto end;
}
if (! Sampled_getWindowSamples (me, xmin, xmax, & imin, & imax)) {
/*
* No sample centres between xmin and xmax.
* Try to return the lesser of the values at these two points.
*/
double fleft = Sampled_getValueAtX (me, xmin, ilevel, unit, interpolate);
double fright = Sampled_getValueAtX (me, xmax, ilevel, unit, interpolate);
if (NUMdefined (fleft) && fleft < minimum) minimum = fleft, xOfMinimum = xmin;
if (NUMdefined (fright) && fright < minimum) minimum = fright, xOfMinimum = xmax;
} else {
for (i = imin; i <= imax; i ++) {
double fmid = my v_getValueAtSample (i, ilevel, unit);
if (fmid == NUMundefined) continue;
if (interpolate == FALSE) {
if (fmid < minimum) minimum = fmid, xOfMinimum = i;
} else {
/*
* Try an interpolation, possibly even taking into account a sample just outside the selection.
*/
double fleft = i <= 1 ? NUMundefined : my v_getValueAtSample (i - 1, ilevel, unit);
double fright = i >= my nx ? NUMundefined : my v_getValueAtSample (i + 1, ilevel, unit);
if (fleft == NUMundefined || fright == NUMundefined) {
if (fmid < minimum) minimum = fmid, xOfMinimum = i;
} else if (fmid < fleft && fmid <= fright) {
double y [4], i_real, localMinimum;
y [1] = fleft, y [2] = fmid, y [3] = fright;
localMinimum = NUMimproveMinimum (y, 3, 2, NUM_PEAK_INTERPOLATE_PARABOLIC, & i_real);
if (localMinimum < minimum)
minimum = localMinimum, xOfMinimum = i_real + i - 2;
}
}
}
xOfMinimum = my x1 + (xOfMinimum - 1) * my dx; /* From index plus phase to time. */
/* Check boundary values. */
if (interpolate) {
double fleft = Sampled_getValueAtX (me, xmin, ilevel, unit, TRUE);
double fright = Sampled_getValueAtX (me, xmax, ilevel, unit, TRUE);
if (NUMdefined (fleft) && fleft < minimum) minimum = fleft, xOfMinimum = xmin;
if (NUMdefined (fright) && fright < minimum) minimum = fright, xOfMinimum = xmax;
}
if (xOfMinimum < xmin) xOfMinimum = xmin;
if (xOfMinimum > xmax) xOfMinimum = xmax;
}
if (minimum == 1e301) minimum = xOfMinimum = NUMundefined;
end:
if (return_minimum) *return_minimum = minimum;
if (return_xOfMinimum) *return_xOfMinimum = xOfMinimum;
}
