In the elimination method of solving linear equations,pivot in an elimination step is a element with maximum-mod. 在解线性方程组的消元法中，主元素指在某步消元时模最大的那个元素。
Major and trace element geochemical data show that this deposit was formed in a restricted aulacogen against the setting of an active continental margin. 沉积岩的主元素和特征微量元素地球化学研究表明，该矿床形成于活动大陆边缘的局限裂陷海盆环境。
