Wrong irr values

[mohit-bn]

We are getting very different irr values for slightly different cashflows.

cf1
out[16]: 
array([-1.44852555e+08,  1.28859998e+06,  1.27305118e+06,  1.25407349e+06,
        1.24199669e+06,  1.22647792e+06,  1.21095552e+06,  1.19206955e+06,
        1.17989821e+06,  1.16436524e+06,  1.14883185e+06,  1.12945217e+06,
        1.11780102e+06,  1.10228427e+06,  1.08671783e+06,  1.06755759e+06,
        1.05502327e+06,  1.03885451e+06,  1.02247003e+06,  1.00227444e+06,
        9.88024873e+05])
cf2
Out[17]: 
array([-1.44852555e+08,  1.41881733e+06,  1.40267049e+06,  1.38296290e+06,
        1.37042160e+06,  1.35430596e+06,  1.33818655e+06,  1.31857419e+06,
        1.30593472e+06,  1.28980433e+06,  1.27367350e+06,  1.25354845e+06,
        1.24144917e+06,  1.22533563e+06,  1.20917048e+06,  1.18927331e+06,
        1.17625690e+06,  1.15946627e+06,  1.14245161e+06,  1.12147927e+06,
        1.10668164e+06])

pyxirr.irr(cf1), pyxirr.irr(cf2)
Out[19]: (-0.13854127397889382, -1.761587679320197)
# comparison with numpy_financial
npf.irr(cf1), npf.irr(cf2)
Out[18]: (-0.13854127397889426, -0.1320937225730502)

[Anexen]

Hi, @mohit-bn. Thank you for submitting an issue. I agree that the result is a bit confusing.
Which pyxirr version do you use? The latest version gives me -1.761587679256444, a bit different value. Strictly speaking, -1.761587679256444 is the correct answer, because the function has two roots.
I'm currently working on improving IRR and I'm going to give the higher priority to a value closer to 0.

[mohit-bn]

thanks @Anexen giving higher priority to value closer to 0 sounds good. We are using "0.7.3" version

[Anexen]

Hi @mohit-bn. Fixed in v0.9.3