Quadruple-precision floating-point format special characteristics: In addition to the double-double arithmetic, it is also possible to generate triple-double or quad-double arithmetic if higher precision is required without any higher precision floating-point library. They are represented as a sum of three (or four) double-precision values respectively. They can represent operations with at least 159/161 and 212/215 bits respectively. A similar technique can be used to produce a double-quad arithmetic, which is represented as a sum of two quadruple-precision values. They can represent operations with at least 226 (or 227) bits. Quadruple precision is often implemented in software by a variety of techniques (such as
Owned-and-operated television stations in the United States opened up a new spectrum of frequencies on the UHF dial (channels 14–83) for terrestrial television. As an incentive for companies to operate UHF stations, the FCC relaxed the ownership limit for a given entity from five to seven stations, provided that no more than five were on the VHF dial. With this opportunity to expand its roster of O&Os, NBC bought WBUF-TV (channel 17) in Buffalo in 1955 and WKNB-TV (channel 30) in New Britain, Connecticut (near Hartford) in 1957, and changed WKNB's call letters to WNBC-TV (the present-day WNBC in New York City used the WRCA-TV callsign from