Counting rods (simplified Chinese: 筹; traditional Chinese: 籌; pinyin: chóu; Japanese: 算木, sangi) are small bars, typically 3–14 cm long, used by mathematicians for calculation in ancient China, Japan, Korea, and Vietnam. They are placed either horizontally or vertically to represent any number and any fraction.
The written forms based on them are called rod numerals. They are a true positional numeral system with digits for 1-9 and a blank for 0, from the Warring states period to the 16th century.
Read more about Counting Rods: History, Using Counting Rods, Rod Numerals
Famous quotes containing the words counting and/or rods:
“But counting up to two
Is harder to do....”
—Philip Larkin (1922–1986)
“At length, having come up fifty rods off, he uttered one of those prolonged howls, as if calling on the god of loons to aid him, and immediately there came a wind from the east and rippled the surface, and filled the whole air with misty rain, and I was impressed as if it were the prayer of the loon answered, and his god was angry with me; and so I left him disappearing far away on the tumultuous surface.”
—Henry David Thoreau (1817–1862)