# [uf-new] Measurement brainstorming (was: Measure & currency)

Andy Mabbett andy at pigsonthewing.org.uk
Fri Sep 28 08:29:30 PDT 2007

```In message
<e86992a40709280700w3f0a110etee6409cbd74692d4 at mail.gmail.com>, Frances
Berriman <fberriman at gmail.com> writes

>On 28/09/2007, Andy Mabbett <andy at pigsonthewing.org.uk> wrote:
>
>> I think we could, if we put our collective mines to it, have first-draft
>> currency (even if only for current, decimal currencies) and measurement
>> (even if only for metric values) microformat in a few weeks (and, again,
>> doing so before Firefox 3 goes live would be A Good Thing [TM]). Surely
>> no-one can deny the evidence that such data is widely published?
>
>Okay.  I'm following you on this.   Recipe will definitely need
>weights and measures in some form, so lets look at that in it's self
>first in it's simplest form, after all a recipe pretty much is just 2
>things (a list of stuff you need and how to put that stuff together).

At its simplest form, measure can be:

<span class="hmeasure">
<span class="quantity">[number]</span>
<span class="unit">[SI unit]</span>
</span>

Where SI unit is, for example, "kg"; or "kilogram". SI units are listed
at:

<http://en.wikipedia.org/wiki/SI_base_unit>

<http://en.wikipedia.org/wiki/SI_derived_unit>

Which leaves the issues:

*    Common, non-SI names of units

*    Compound units ("meters per second")

*    Units with superscripts. e.g. square metres

*    Case-sensitivity (S = electrical conductance; s= seconds)

Given the above, and publishing good practice, perhaps units should be
marked up as:

<abbr class="unit" title="kilogram">kg</abbr>

<abbr class="unit" title="kilogram">kilo.</abbr>

<abbr class="unit" title="newton-second">N.s</abbr>

<abbr class="unit"
title="kilogram-per-cubic-metre">kg/m<sup>3</sup>
</abbr>

maybe with plural values allowed:

<abbr title="kilograms">kg</abbr>

We can later consider:

*    How do we deal with non-metric units ("miles", "inches")

*   do standard names/ abbreviations exist?

*   what about, for example, imperial vs. US Gallons

Parser writers could choose to recognise only metric units, or only
simple units (so kilometre, but not "newton-second").

This system would be extensible, as publishers and parsers could use
other units, and parsers SHOULD ignore any they don't know.

(The above can be considered a "straw man".)

>I think there is value in correctly marking weight/volume values for
>various interesting purposes (conversion, ordering, comparison etc.)
>in a recipe.  We'll work out when we've done the recipe research work
>whether it's actually appropriate to use "measure" or "currency" when
>we get to that stage of the process.

My mention of "currency" was not in relation to recipe; I'll comment
further in a separate post, to sub-divide the thread by topic

...though currency could be a subset of "hMeasure", with currency codes
as units:

<span class="hmeasure">
<abbr class="unit" title="USD">\$</abbr>
<span class="quantity">5</span>
</span>

>There's hardly any examples for measure at the moment, so there's a
>fair bit of work to be done there (nothing for recipes at least,
>unless you want to say how fast your eggs were laid!).

It shouldn't take long to find examples of measurements on-line; there
are rather a lot; but we should also bear in mind that standards for

>I also concur with the difficulty of saying what a "pinch", "handful",
>"to taste" or "as necessary" (and many others) will end up equating
>too.

That's specific to recipes, rather than measurements in general.

>Recipes aren't necessarily concrete values so we'll have to be
>aware of this and not force authors into publishing data they weren't