Flute acoustics: measurement, modelling and design - School of ...

APPENDIX B. PROGRAM LISTINGS 251
m->R_min_df = searche->f - e->f;
m->R_min_dZ = searche->Z - e->Z;
break;
}
}
/* if none found, set to nan */
if(j >= sizeVector(extv)) {
m->R_min_df = invalidNum();
m->R_min_dZ = invalidNum();
}
/* add minimum to minimum vector */
addElement(minv, m);
}
}
/* set the harmonic details of all minima in vector */
harmonicity(minv);
}
return minv;
Vector extrema(Vector allpoints) {
int i, j;
int seq_inc, seq_dec;
int descent, ascent;
Extremum e;
Point p;
Vector extv = createVector();
Vector points = createVector();
/* load vector of points with the initial portion of data.
All points are equal to the first point in the data. */
for(i = 0; i < NUM_POINTS; i++) {
p = (Point)malloc(sizeof(*p));
*p = *((Point)elementAt(allpoints, 0));
addElement(points, p);
}
/* initialise flags */
seq_inc = 0;
seq_dec = 0;
descent = 0;
ascent = 0;
/* progress points one at a time till end of data set */
for(i = 0; progressPoints(points, allpoints, i); i++) {
/* if graph increases... */
if(((Point)elementAt(points, sizeVector(points) - 1))->y
> ((Point)elementAt(points, sizeVector(points) - 2))->y) {
/* tally number of points increased ... set flag when
we have moved up far enough to expect minimum/maximum */
seq_inc+=2;
if(seq_inc/2 >= TWEAK)
ascent = 1;
if(seq_dec/2 > 0)
seq_dec-=2;