1.32+: inaccurate value reports caused by low precision P amounts

[akanshaG42]

Hi, seems like transactions are not balances with multiple commodities, potentially due to rounding issue.

b.journal

D R1,23,45,678.0 ; defualt currency of R

P 2023-09-15 USD 83.1 ; USD to R on 09/15

2023-09-15
    assets:equity:acme    66 acme @ 10.2 USD
    income:acme:rsu

Now if I want to see the balance in R, as per docs I will have to pass the and --infer-market-prices and --value=then,R so that purchase/cost price is used.

$ ~/Downloads/hledger-linux-x64/hledger -f b.journal bal   --infer-market-prices --value=then,R

           R55,941.6  assets:equity:acme
          R-55,942.9  income:salary:acme
--------------------
               R-1.3

The -1.3 seems unexpected. The posting are completely balanced if I use round numbers.

b.journal

D R1,23,45,678.0 ; defualt currency of R

P 2023-09-15 USD 83 ; USD to R on 09/15

2023-09-15
    assets:equity:acme    66 acme @ 10 USD
    income:salary:acme

$ ~/Downloads/hledger-linux-x64/hledger -f b.journal bal  --infer-market-prices --value=then,R

           R54,780.0  assets:equity:acme
          R-54,780.0  income:salary:acme
--------------------
                   0

I have gone through the manual sections of Cost and Value reporting as well as the Track Investments cookbook multiple time and seems like the command line flags are correct.

Though I have been using hledger for many years, this is the first time I have to deal with foreign stocks and equity, so it is completely possible that I am doing something wrong.

Would appreciate any help.

Thanks!

Version Info

$ ~/Downloads/hledger-linux-x64/hledger --version

hledger 1.40, linux-x86_64

[simonmichael]

Hi @akanshaG42, thanks for the report. I must admit I'm not seeing an explanation just yet!

Here's a simpler example:

P 2023-09-15 USD R100

2023-09-15
    assets    50 acme @ 10 USD
    income

The postings will have the same cost (by definition), and if valued with the same market prices, should also have the same value:

$ hledger print -x
2023-09-15
    assets    50 acme @ 10 USD
    income            -500 USD

$ hledger print -x --infer-market-prices -X R
2023-09-15
    assets          R50000
    income         R-50000

I can change the price and/or cost to any integer and the posting values still match.
But if I give both price and cost some non-zero decimal digits,

P 2023-09-15 USD R100.5

2023-09-15
    assets    50 acme @ 10.5 USD
    income

the postings are valued differently:

$ hledger print -x
2023-09-15
    assets    50 acme @ 10.5 USD
    income            -525.0 USD

$ hledger print -x --infer-market-prices -X R
2023-09-15
    assets          R52760
    income       R-52762.5

I expected both postings to be valued at R52762.5.

[simonmichael]

A simpler case:

P 2000-01-01 USD R 100.5

2000-01-01
    (a)    50 ACME @ 10.5 USD

And it turns out to be a regression, since hledger 1.32:

$ hledger-1.31 print --infer-market-prices -X R
2000-01-01
    (a)       R 52762.5

$ hledger-1.32 print --infer-market-prices -X R
2000-01-01
    (a)         R 52760

During the chain of (two) conversions, an intermediate value is inappropriately rounded to the precision of the P directive's amount (one decimal place), causing inaccuracy.

You can work around it for now by making sure P amounts have enough decimal digits. Eg for this example, changing it to P 2000-01-01 USD R 100.50 makes the problem go away.

Thank you @akanshaG42! Please claim your $50 https://hledger.org/REGRESSIONS.html#regression-bounty when convenient.

[simonmichael]

This is fixed in master.
(Linux x64 binary here if it helps.)

[akanshaG42]

Thank you for an incredibly fast turn around here @simonmichael. I tried the CI build with my actual ledger and it is balanced now. Thanks again!

[simonmichael]

Hi @akanshaG42, I encourage you to claim your $50 regression finder's bounty within the next 7 days! If not, it will be recorded as a project donation.
https://hledger.org/REGRESSIONS.html#regression-bounty

[akanshaG42]

Hi @akanshaG42, I encourage you to claim your $50 regression finder's bounty within the next 7 days! If not, it will be recorded as a project donation. https://hledger.org/REGRESSIONS.html#regression-bounty

That's alright @simonmichael. Please consider it as a project donation.