How to Calculate the Partial Differential of 4 Momentum ？

[iisiaccNewton]

hello FeynCalc
Can we calculate the partial differential in the following figure ？

If this function does not exist, how to add some custom functions ?

[iisiaccNewton]

I found that the following code runs very well, but I don't know how to add it into FeynCalc. It is very troublesome to run this code before each calculation.
{
pd[FV[p_, b_], p_, a_] := MT[a, b];
pd[GS[p_], p_, a_] := GA[a];
pd[SP[p_], p_, a_] := 2 FV[p, a];
pd[SP[p_, k_], p_, a_] := FV[k, a];
pd[f1_ + f2_, p_, a_] := pd[f1, p, a] + pd[f2, p, a];
pd[f_^n_, p_, a_] := n*f^(n - 1)*pd[f, p, a];
pd[f1_*f2_, p_, a_] := pd[f1, p, a]f2 + f1pd[f2, p, a];
pd[Dot[f1_, f2_], p_,
a_] := (Dot[pd[f1, p, a], f2] +
Dot[f1, pd[f2, p, a]]) /. {Dot[, 0, ] :> 0,
Dot[s, g + c, h__] :> Dot[s, g, h] + Dot[s, c, h]};
pd[f_, p_, a_] := If[FreeQ[f, p], 0, pd[f, p, a]];

}

Here is an example.

[vsht]

FourDivergence should be sufficient https://feyncalc.github.io/FeynCalcBookDev/FourDivergence.html Am 10.04.24 um 12:54 schrieb Isaac Newton:

…

I found that the following code runs very well, but I don't know how to add it into FeynCalc. It is very troublesome to run this code before each calculation. { pd[FV[p_, b_], p_, a_] := MT[a, b]; pd[GS[p_], p_, a_] := GA[a]; pd[SP[p_], p_, a_] := 2 FV[p, a]; pd[SP[p_, k_], p_, a_] := FV[k, a]; pd[f1_ + f2_, p_, a_] := pd[f1, p, a] + pd[f2, p, a]; pd[f_^n_, p_, a_] := n*f^(n - 1)*pd[f, p, a]; pd[f1_*f2_, p_, a_] := pd[f1, p, a]/f2 + f1/pd[f2, p, a]; pd[Dot[f1_, f2_], p_, a_] := (Dot[pd[f1, p, a], f2] + Dot[f1, pd[f2, p, a]]) /. {Dot[///, 0, /*] :> 0, Dot[s*/, g/ + c/, h/__] :> Dot[s, g, h] + Dot[s, c, h]}; pd[f_, p_, a_] := If[FreeQ[f, p], 0, pd[f, p, a]]; } Here is an example. 2024-04-10.185351.png (view on web) <https://github.com/FeynCalc/feyncalc/assets/112673778/fab4fdff-1940-4952-9c2f-32b442558482> — Reply to this email directly, view it on GitHub <#260 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABXSD5AKM2MSZOHYP6SESVDY4UK7XAVCNFSM6AAAAABF62GSSKVHI2DSMVQWIX3LMV43SRDJONRXK43TNFXW4Q3PNVWWK3TUHM4TANRZG44DS>. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[iisiaccNewton]

I find the function names you define very confusing, which often makes it difficult for me to find them when consulting manuals.
in this example,i think defining function names as PartialD is more convenient for searching