Comment by lucgommans | Hacker News Reader

Comment by lucgommans | Hacker News Reader

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Rather than teaching a separate utility, I would recommend qalc which has unit conversions built in :)

    $ qalc -t 100km/h / 0.956s to gee
    2.9629132 gees

(where -t is for terse mode; by default it expands unit abbreviations and adds parentheses so you see whether it did what you wanted)

The reason I recommend it is because it does so much more, I really love this utility since discovering it about a year ago. Example of using time notation combined with uncertainty and unit conversion:

    > (18:41 - 09:00+/-00:30) hours * 250 W to kWh
      (((1121 / 60) - (9±0.5)) * hour) * (250 * watt) =
      approx. (2.4208333±0.125) kW*h

The irony of advocating against a "separate utility", and then promoting a separate utility...

You never use a calculator?

I use calculators plenty, but I neither have that one installed nor use it. On my PC, I use either grpn or units. More often, I pull out my HP 48G+.

GRPN for anyone else who doesn't know it: http://lashwhip.com/grpn.html

What I meant to say is that, if one uses a featureful calculator like qalc, then you get unit conversion included without needing two separate utilities. Of course, if you've used a(n obscure) calculator for decades then it may be easier to learn to use a separate unit convertor instead

I wouldn't exactly call the HP "obscure", but it does support unit calculations too. And "units" is more than plenty when I want infix operations.

In my usage, GNU units appears to be more featureful than qalc. For example I noticed that qalc lacks many definitions that I often use, such as energy density (eg. "gasoline"), mass density (eg. "golddensity"), energy units (eg. "therm"), astronomy (eg. "earthradius", "solarmass"), etc. And GNU units works just fine as a calculator.

So, from my viewpoint, qalc is the "separate utility" that I don't need ;-)

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