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When I use the following orders to calculate oneloop feynman integral by FIREBurn, the result contains a strange sign "var2". And I calculate the same integral by FIRE5, confirm that var2=MC. What's more, the configure file "FIREp1.m" show that var2=MC.

Exit[]
$LoadAddOns = {"FeynHelpers"};
<< FeynCalc`;
ScalarProduct[p1, p1] = 4 MB^2;
ScalarProduct[p2, p2] = 0;
ScalarProduct[p1, p2] = 2 (MB^2 - MC^2);
fad = FAD[{q, MC, 2}, {q - p1, MC}, {q - p2, MC, 2}]
FIREBurn[fad, {q}, {p1, p2}]

-(((D-2) (D^2 MB^2+D^2 MC^2-11 D MB^2-10 D MC^2+31 MB^2+24 MC^2))/(64 (D-5) MC^4 (MC-MB)^3 (MB+MC)^3 ((q-p1)^2-MC^2)))-((D-2) (2 D^2 MB^4+4 D^2 MB^2 MC^2-16 D MB^4-25 D MB^2 MC^2-D MC^4+32 MB^4+26 MB^2 MC^2+4 MC^4))/(128 MC^6 (MC-MB)^3 (MB+MC)^3 (q^2-MC^2))+((D-2) (4 D^3 MB^2 var2^2+2 D^3 MC^4+4 D^2 MB^4-51 D^2 MB^2 MC^2-29 D^2 MC^4-36 D MB^4+209 D MB^2 MC^2+141 D MC^4+80 MB^4-272 MB^2 MC^2-228 MC^4))/(128 (D-5) MC^6 (MC-MB)^3 (MB+MC)^3 ((q-p2)^2-MC^2))-((D-4) (2 D MB^2-11 MB^2+MC^2))/(8 MC^2 (MC-MB)^2 (MB+MC)^2 ((q-p2)^2-MC^2).(q^2-MC^2).((q-p1)^2-MC^2))-((D-3) (2 D-11) MB^2)/(16 MC^2 (MB-MC)^3 (MB+MC)^3 (q^2-MC^2).((q-p1)^2-MC^2))

The new partial fractioning library presented in https://arxiv.org/pdf/2008.13194.pdf
seems like a good motivation to add an interface to Singular CAS

In fact, such an interface for older Mma versions already exists

https://www3.risc.jku.at/research/combinat/software/Singular/

and is open source, so that one could fork it and keep only the needed functionality.

I execute the function LToolsEvaluate to test the relevant examples, but I obtain a wrong result. My code is as follows:

Out[6] gives a wrong result different from both FeynHelpers manual and Package-X. I am using Ubuntu 22.04 and Mathematica 13.3, with FeynCalc 10.0.0. Does the mistake involve these software versions? Or are there any specific considerations I should be aware of?

When I used FIREBurn on Windows system, some errors occurred. Here is my code:

$LoadAddOns = {"FeynHelpers"};
<< FeynCalc`
FAD[{q, m, 4}]
FIREBurn[%, {q}, {}]

And my errors are:

Syntax::stresc :  Unknown string escape \U.
Syntax::stresc :  Unknown string escape \g.
Syntax::stresc :  Unknown string escape \A.
Syntax::stresc :  Unknown string escape \R.
Syntax::stresc :  Unknown string escape \M.
Syntax::stresc :  Unknown string escape \A.
Syntax::stresc :  Unknown string escape \F.
Syntax::sntx: Invalid syntax in or before "Get["C:\Users\guoji\AppData\Roaming\Mathematica\Applications\FIRE5\FIRE5.m"];"
                                                  ^
     (line 3 of "C:\Users\guoji\AppData\Roaming\Mathematica\Applications\FeynCalc\Database\FIREp1-int1.m").

As you can see, every unknown string comes from the first letter of every directory. I tried to fix this issue. I came into file 'FIREp1-int1.m' and rewrite every directory like '"C:\Users\guoji\AppData\...' and then it give me right answers with little warning.

I tried same code on Mac and Linux system. It worked well and there was not error.

Maybe you can fix this problem. Or tell me how to deal with it. Thx!!!

Dear FeynCalc Authors,
Using FCFAConvert with a Feynarts model file that contains Majorana Fermions does not work.
It appears that MajoranaSpinor is not recognized by FeynCalc.

please advise,
best,

Kirtimaan