Double stop Double stop In music, a double stop refers to the technique of playing two notes simultaneously on a stringed instrument such as a violin, a guitar, a cello, or a double bass. In performing a double stop, two separate strings are bowed or plucked simultaneously. Although the term itself suggests these strings are to be fingered (stopped), in practice one or both strings may be open. A triple stop is the same technique applied to three strings; a quadruple stop applies to four strings. Double, triple, and quadruple stopping are collectively known as multiple stopping. Early extensive examples of the
Quadruple-precision floating-point format the double-double technique above, although that technique does not implement IEEE quadruple precision), since direct hardware support for quadruple precision is, as of 2016, less common (see "Hardware support" below). One can use general arbitrary-precision arithmetic libraries to obtain quadruple (or higher) precision, but specialized quadruple-precision implementations may achieve higher performance. A separate question is the extent to which quadruple-precision types are directly incorporated into computer programming languages. Quadruple precision is specified in Fortran by the codice_2 (module codice_3 from Fortran 2008 must be used, the constant codice_4 is equal to 16 on most processors), or as codice_5, or in