Name: Vladyslav Shtabovenko Date: 01/16/16-11:45:42 PM Z

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Thanks. The correct syntax should be however

LC[][q, k2, p1, p3]^3 // Contract

since LC[a,b,c,d] means eps^{a b c d} while

LC[][a,b,c,d] stands for eps^{mu nu rho si} a_mu b_nu c_rho d_si

Anyhow, the bug is now fixed,

https://github.com/FeynCalc/feyncalc/commit/f8ccd75547c6c10abee583ca55b1f42e62bac900

just rerun the stable installer and click yes when it asks you for
permission to overwrite the existing version:

Import[“https://raw.githubusercontent.com/FeynCalc/feyncalc/master/install.m”]
InstallFeynCalc[]

Cheers,
Vladyslav

Am 13.01.2016 um 17:23 schrieb ZYJ:
> In[164]:= LC[q, k2, p1, p3]^3 // Contract
>
> \:6B63\:5728\:8BA1\:7B97In[164]:= Eps::argrx: Eps[{LorentzIndex[q], LorentzIndex[k2], LorentzIndex[p1], LorentzIndex[p3], OptionsPattern[Eps]}] called with 5 arguments; 4 arguments are expected.
>
> Out[164]= -24 Null
>

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