目前,一些ISO国际标准资料在长度计量时,常给出公制和英制两种尺寸,其尺寸又是以公制为基础、英制服从于公制(即英制尺寸常为近似值)的;在英制尺寸中使用的又是英制小数,其间换算起来比较麻烦,因此很需要一种毫米换算成英制小数的用表。另外,在测绘国外样机时,也经常遇到公、英制长度数据的换算问题,而近年来这一工作的量又较以前为大,也很需要这样的表,特别是毫米与英制小数对照表在很多资料里均是难以查到的,考 At present, some ISO international standard materials are often measured in length in both metric and imperial sizes. The dimensions are based on the metric system, and the British uniform is from the metric system (ie, the English system size is often an approximate value); in the inch size The use of an imperial decimal again, which is cumbersome to convert, requires a table with millimeters converted to imperial decimals. In addition, in the mapping of foreign prototypes, the conversion of length data in both public and imperial systems is also frequently encountered. In recent years, the amount of this work has been larger than before, and such tables are also very much needed, especially the millimeter and inch decimal tables. It is difficult to find in many materials.