若尔当测度

若尔当测度(英语:Jordan measure)是面积测度方式,数学家卡米尔·若尔当所提出。设E是中的一个有界集,而f是在E上取值为1的函数,如果f在E上可积,则称E为Jordan可测的(可求体积的)。并且记,称为E的Jordan测度,也就是E的体积。

A simple set is, by definition, a union of (possibly overlapping) rectangles.
The simple set from above decomposed as a union of non-overlapping rectangles.