Function: intformal
Section: polynomials
C-Name: integ
Prototype: GDn
Help: intformal(x,{v}): formal integration of x with respect to v, or to the
 main variable of x if v is omitted.
Doc: \idx{formal integration} of $x$ with respect to the main variable if $v$
 is omitted, with respect to the variable $v$ otherwise. Since PARI does not
 know about ``abstract'' logarithms (they are immediately evaluated, if only
 to a power series), logarithmic terms in the result will yield an error. $x$
 can be of any type. When $x$ is a rational function, it is assumed that the
 base ring is an integral domain of characteristic zero.
