It held a table of successive columns which delimited the successive orders of magnitude of their sexagesimal (base 60) number system. The Sumerian abacus appeared between 27 BC. The user of an abacus is called an abacist. īoth abacuses and abaci are used as plurals. Greek ἄβαξ probably borrowed from a Northwest Semitic language like Phoenician, evidenced by a cognate with the Hebrew word ʾābāq ( אבק), or "dust" (in the post-Biblical sense "sand used as a writing surface"). While the table strewn with dust definition is popular, some argue evidence is insufficient for that conclusion. Alternatively, without reference to ancient texts on etymology, it has been suggested that it means "a square tablet strewn with dust", or "drawing-board covered with dust (for the use of mathematics)" (the exact shape of the Latin perhaps reflects the genitive form of the Greek word, ἄβακoς ( abakos)). The Latin word is derived from ancient Greek ἄβαξ ( abax) which means something without a base, and colloquially, any piece of rectangular material. The word abacus dates to at least AD 1387 when a Middle English work borrowed the word from Latin that described a sandboard abacus. The abacus is still used to teach the fundamentals of mathematics to children in most countries. Others may use an abacus due to visual impairment that prevents the use of a calculator. The abacus remains in common use as a scoring system in non- electronic table games. Merchants, traders, and clerks in some parts of Eastern Europe, Russia, China, and Africa use abacuses. The abacus has an advantage of not requiring a writing implement and paper (needed for algorism) or an electric power source. Although calculators and computers are commonly used today instead of abacuses, abacuses remain in everyday use in some countries. In the ancient world, abacuses were a practical calculating tool. The beads are first arranged to represent a number, then are manipulated to perform a mathematical operation with another number, and their final position can be read as the result (or can be used as the starting number for subsequent operations). 1⁄ 2, 1⁄ 4, and 1⁄ 12 in Roman abacus), and a decimal point can be imagined for fixed-point arithmetic.Īny particular abacus design supports multiple methods to perform calculations, including addition, subtraction, multiplication, division, and square and cube roots. Natural numbers are normally used, but some allow simple fractional components (e.g. Roman and East Asian abacuses use a system resembling bi-quinary coded decimal, with a top deck (containing one or two beads) representing fives and a bottom deck (containing four or five beads) representing ones. Later the beads were made to slide on rods and built into a frame, allowing faster manipulation.Įach rod typically represents one digit of a multi-digit number laid out using a positional numeral system such as base ten (though some cultures used different numerical bases). In their earliest designs, the beads could be loose on a flat surface or sliding in grooves. The abacus consists of a two-dimensional array of slidable beads (or similar objects). The abacus ( PL: abaci or abacuses), also called a counting frame, is a hand-operated calculating tool of unknown origin used since ancient times in the ancient Near East, Europe, China, and Russia, millennia before the adoption of the Hindu-Arabic numeral system. For the medieval book, see Liber Abaci.īi-quinary coded decimal-like abacus representing 1,352,964,708
0 kommentar(er)
