A formula for IRR

[akmon]

I use SOLVE and no problem in CAS or HOME, with my physical calculator.
Also the list autostores the values in CAS and HOME without sto command.
And I don´t see any problem if the list doesn´t exists. L1 always exists, with 0 items but it exists. Then you enter the flows and that´s all. Try this again:

Code:

EXPORT TIR()
BEGIN
EDITLIST(L1,"TASA INTERNA DE RETORNO");
SOLVE(ΣLIST(MAKELIST((L1(I)/X^(I-1)),I,1,SIZE(L1))),X)-1;
END;

Erase all in L1 and start from de beginning. Tha program starts with EDITLIST menu, ready for input data.