农业科学研究中有数据記录和結果运算。在記录数据和計算結果时,有人总是在小数点后尽量放数字;以为位数愈多,就愈精确。其实,这样做是不对的。数据記录和結果运算是有規則的,在什么情况下一个記录数字或运算数字用几位,有一定規定,不可乱用。这就是术語上所说的要注意“有效数字”。一、什么是有效数字有效数字是一种用来指示数量的数字。若以刻度为一度的溫度计测量溫度,溫度为五点几度,在溫度計上只能讀到五度,点几度是要估計的。尽管这点几度是可疑的(因为它是估計的),但它仍有意义。例如,摄氏五点五度,这五点五中的每个数字都有意义,称为有效数字。在这种情况下,如果把測得 There are data records and results operations in agricultural science research. When recording data and calculating results, someone tries to put numbers after the decimal point as much as possible; the more exactly the digits, the more accurate it is. In fact, this is wrong. Data records and the results of the operation is a rule, under what circumstances a record number or operation figures with a few, there are certain provisions, can not be used indiscriminately. This is what the terminology says about “significant digits.” First, what is the effective number Effective number is a number used to indicate the number. If the scale for the degree of thermometer temperature measurement, the temperature of five o’clock, the thermometer can only read five degrees, a few degrees is to be estimated. Although this is a bit suspicious (because it is estimated), it still makes sense. For example, at 5.5 degrees Celsius, each of the five-fifths makes sense and is called a significant figure. In this case, if measured