log(0.5) and the OS X calculator

The OS X calculator is one of my favorite applications and I use it every day for work (I find  the binary display in the programmer view especially useful). So I was very surprised when I noticed that it was giving me the wrong answer for log(0.5). I was getting log(0.5) = 0.301 when it should be -0.301. Strangely 1-log(0.5) was correctly shown as 1.301. Well today I discovered that this only happens if you enable “Show Separators” in  the View menu.

Does anyone else see this or is it just me?

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  1. John, the mind boggles that you had the misfortune to run into such an obscure bug.

    I confirm the same behaviour with my 10.5.4 system.

    well done, I’m sure Mr. Jobs will have a free gadget winging it’s way to you 😉


  2. john


    FWIW there was no need to get all clever with your logs. With show separators enabled the calculator incorrectly displays any number > -1 and < 0.

    Maybe its a feature? 🙂


  3. zooloo

    A calculator is supposed to be reliable. Whilst slight deviations due to rounding errors cannot be avoided, a single result being *that* far off already renders the calculator moot. And there’s a lot more. Switch to scientific view and try e. g.
    Such a shame. I’d rather ship OS X without any calc than fool the users with crap like this.

  4. Joao

    this is bug #5773447 in Apple’s bug DB. Let’s hoope they fix it soon.

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