Function: mfetaquo
Section: modular_forms
C-Name: mfetaquo
Prototype: G
Help: mfetaquo(eta): modular form corresponding to the eta quotient matrix
 eta, with a possible power of q removed: let v be the valuation at infinity
 of the eta quotient. If v is nonnegative, the result is the eta quotient
 divided by q to the power the fractional part of v. If v is negative,
 the result is the eta quotient divided by q to the power -v, i.e., with
 valuation 0.
Doc: modular form corresponding to the eta quotient matrix \kbd{eta}, with
 a possible power $q^a$ removed: if $v$ is the valuation at infinity
 of the eta quotient, then $a$ is the fractional part of $v$ if $v\ge0$,
 and $a=-v$ if $v<0$, so that in this case the result has valuation $0$.
 \bprog
 ? mfcoefs(mfetaquo(Mat([1,1])),8)
 %1 = [1, -1, -1, 0, 0, 1, 0, 1, 0]
 ? mfcoefs(mfetaquo(Mat([1,24])),5)
 %2 = [0, 1, -24, 252, -1472, 4830, -6048]
 @eprog
