Examples, non-planar massless 2-loop vertex

Case 1: Additional PR[k1 + p2, 0, n7], with n7=-1+eta

<<AMBREv3.1.1.m

<<PlanarityTestv1.2.m

invariants={p1^2->0,p2^2->0,p1*p2->s/2};

prs=PR[k1,0,n1] PR[k1-k2,0,n2] PR[k2,0,n3] PR[k1-k2+p1,0,n4] PR[k2+p2,0,n5] PR[k1+p1+p2,0,n6];

PlanarityTest[{prs},{k1,k2},DrawGraph->True];

res=MBreprNP[{1},{prs*PR[k1+p2,0,n7]},{k1,k2}]

finres = res/.{n1->1,n2->1,n3->1,n4->1,n5->1,n6->1,n7->-1+eta}

(* 
In the above: (((-s))^(-1-2 eps-eta-z2)) (s^z2) =(((-s))^(-1-2 eps-eta))*(((-1))^(-z2)) , see after expansion - will remain just 1/s, as expected.
*)

<<MB.m

rules=MBoptimizedRules[finres[[1]],eta->0,{},{eps,eta}]

Step1cont=MBcontinue[finres[[1]],eta->0,rules];

after=MBexpand[Step1cont,1,{eta,0,0}]

integrals=after/.MBint[integrand_,rules_]:>MBcontinue[integrand,eps->0,rules]

ser=MBexpand[integrals,Exp[2*eps*EulerGamma],{eps,0,0}];

MBanalytic=MBmerge[ser]

MBintegrate[MBanalytic,{s->-1}]

Quit[]

FIESTAPath="your fiesta path";Get[FIESTAPath<>"FIESTA4.m"];

UsingQLink=True;UsingC=True;

CurrentIntegratorSettings={{"maxeval","500000"}};

SDEvaluate[UF[{k1,k2},{-k1^2,-(k1-k2)^2,-k2^2,-(k1-k2+p1)^2,-(k2+p2)^2,-(k1+p1+p2)^2,-(k1+p2)^2},{p1^2->0,p2^2->0,p1*p2->s/2,
s->-1}],{1,1,1,1,1,1,-1},0]

(* 
Overall sign difference with MB due to different convention in propagators definition. 
Also be careful with using Fiesta and MB-suite in one Mathematica session, may lead to errors
*)

Quit[]

Case 2: PR[k2 + p1, 0, n7], with n7=-1+eta

<<AMBREv3.1.1.m

<<PlanarityTestv1.2.m

invariants={p1^2->0,p2^2->0,p1*p2->s/2};

prs=PR[k1,0,n1] PR[k1-k2,0,n2] PR[k2,0,n3] PR[k1-k2+p1,0,n4] PR[k2+p2,0,n5] PR[k1+p1+p2,0,n6];

PlanarityTest[{prs},{k1,k2},DrawGraph->True];

res=MBreprNP[{1},{prs*PR[k2+p1,0,n7]},{k1,k2}]

finres = res/.{n1->1,n2->1,n3->1,n4->1,n5->1,n6->1,n7->-1+eta}

<<MB.m

rules=MBoptimizedRules[finres[[1]],eta->0,{z2>z1},{eps,eta}]

Step1cont=MBcontinue[finres[[1]],eta->0,rules];

after=MBexpand[Step1cont,1,{eta,0,0}]

integrals=after/.MBint[integrand_,rules_]:>MBcontinue[integrand,eps->0,rules]

ser=MBexpand[integrals,Exp[2*eps*EulerGamma],{eps,0,0}];

MBanalytic=MBmerge[ser]

MBintegrate[MBanalytic,{s->-1}]

Quit[]

FIESTAPath="your fiesta path";Get[FIESTAPath<>"FIESTA4.m"];

UsingQLink=True;UsingC=True;

CurrentIntegratorSettings={{"maxeval","500000"}};

SDEvaluate[UF[{k1,k2},{-k1^2,-(k1-k2)^2,-k2^2,-(k1-k2+p1)^2,-(k2+p2)^2,-(k1+p1+p2)^2,-(k2+p1)^2},{p1^2->0,p2^2->0,p1*p2->s/2,
s->-1}],{1,1,1,1,1,1,-1},0]

Quit[]