DILOG EXTENDED _ _ _ _ _ _ _ _ _ _ _ _ operator

The package specfn supplies an extended support for the dilog operator which implements the dilogarithm fu nction.

dilog(x) := - defint(log(t)/(t - 1),t,1,x);

syntax:

examples:

defint(log(t)/(t - 1),t,1,x); 

  - dilog (x) 


dilog 2; 

      2
  - pi  /12 



on rounded; 

Dilog 20; 

  - 5.92783972438

The operator Dilog is sometimes called Spence's Integral for n = 2.