American Citizen on Mon, 27 Nov 2023 02:44:41 +0100


[Date Prev] [Date Next] [Thread Prev] [Thread Next] [Date Index] [Thread Index]

asking for a simple locally soluble algorithm for a quartic


Does anyone have a simple GP-Pari script which outputs 0 for false and 1 for true when the input is a quartic in vector format: [a,b,c,d,e] where the quartic is a*x^4 + b*x^3 + c^x^2 + d^x +e and we are trying to find the everywhere_local_solubility of the quartic?

Example GP Pari function:

everywhere_locally_soluble(Q) = [0,1] where 0 means false and 1 means true.

I tried to follow the algorithms in Chapter 3 of Cremona's book on elliptic curve algorithms, but hit difficulty on trying to write down in the GP Pari script the discriminant of a quartic, which forced me to go to Wolfram Mathematica to find this expression, which is horribly complex and incredibly easy to mistype the values from the image graphics file. It is fascinating (in a perverse way) to find that image files are posted for long equations, thus forcing a person to manually transcribe them, and most people have difficulty doing this without transcription error.

I still am stuck in these algorithms in Chapter 3 and trying to successfully transcribe them into GP-Pari script.

I appreciate the assist.

THANK YOU.

Randall