provides several options. In addition to the notation &quot; R_i{}^{jk}{}_l &quot; , common in other applications, additional notations can be used, namely &quot; R_i{}^jk{}_l &quot; and &quot; {{R_i}^jk}_l. &quot;
提供了多种可能性。除了在其他程序中常见的编写方式 &quot; R_i{}^{jk}{}_l &quot; 还可应用其他方法，即 &quot; R_i{}^jk{}_l &quot; 和 &quot; {{R_i}^jk}_l &quot; 。