Name: Jorge Romão Date: 03/02/20-07:32:20 PM Z


Dear Vladyslav

Thanks for the clarification. Now it does exactly what I need.

Best

Jorge

On 02/03/20 16:26, V. Shtabovenko wrote:
> UsePaVeBasis enters the stage only if the input contains
> tensor integrals. In your case there are none, so nothing
> happens.
>
> ToPaVe is applied to any output at the very end, hence, the
> conversion still occurs.
>
> There can be also cases where despite having
> UsePaVeBasis->True you will still get some scalar integrals
> as FADs, since those arose through partial fractioning before
> the actual tensor reduction.
>
> Using
>
> TID[amp,k1,UsePaVeBasis->True, ToPaVe->True]
>
> will ensure that all loop integrals in the output are always written
> as PaVe functions.
>
> Cheers,
> Vladyslav
>
>
>
>
>
> Am 02.03.20 um 17:00 schrieb Jorge C. Rom�o:
>> I am moving from OneLoop to TID. However, consider
>>
>> amp=FAD[{k1, m1}, {k1 - p1, m2}, {k1 - q1, m3}, q2 + q3]
>>
>> which appears in a non irreducible diagram. Now
>>
>> TID[amp,k1,ToPaVe->True]//FCE//InputForm =
>> I*Pi^2*C0[SPD[p1, p1], SPD[q1, q1], SPD[p1, p1] - 2*SPD[p1, q1] +
>> SPD[q1, q1], m2^2, m1^2, m3^2]*FAD[q2 + q3]
>>
>> as it should. However
>>
>> TID[amp,k1,UsePaVeBasis->True]//FCE//InputForm
>> =FAD[q2 + q3]*FAD[{k1, m1}, {k1 - p1, m2}, {k1 - q1, m3}]
>>
>> that is does nothing!
>>
>> This is a piece inserted in a large code and one does not want to
>> look at each term and want to use UsePaVeBasis->True to get fewer terms.
>>
>> Best
>>
>> Jorge
>>
>>
>

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