Girth (tack) often used in addition to a regular leather girth. Made of leather or nylon with an elastic insert (for racing), the overgirth completely encircles the horse around belly and the saddle's seat. It is used by stockmen, eventers, polo players, in flat racing, and by steeplechase jockeys to provide more security in holding the saddle in place. Some girths (those used on jumpers and eventers) have a belly guard (or stud guard), to protect the belly from being stabbed by horseshoe studs as the animal tucks his legs up underneath him over a tall obstacle. The traditional western cinch was
Matroid girth oracle, it is impossible to find the girth using a subexponential number of matroid queries. Similarly, for a real linear matroid of rank , with elements, described by an oracle that gives the orientation of any -tuple of elements, it requires formula_1 oracle queries to determine the girth. Computations using a girth oracle (an oracle that reports the smallest dependent subset of a given set of elements) have also been considered. Matroid girth In matroid theory, a mathematical discipline, the girth of a matroid is the size of its smallest circuit or dependent set. The cogirth of a matroid is