anb955 wrote:
I am looking to have recipes available in both imperial and metric. I would like to be able to put in the imperial and have the "Scaled Amount" come out as a metric number. I cannot find a function for this, and do not know how to input anything into the array. Please help?
Hi anb,
welcome to Apple Discussions and the Numbers '09 forum.
The formula (and the functions) you use will depend on whether you want a mathematical conversion (which can easily lead to overly precise numbers—like the 5' 6" minimum clearance in a parking garage that was re-signed as 1.676 m—correct, but not something you need to know to the thickness of a dime) or a 'practical equivalent' that expresses the amount in terms of the closest similar quantity in general use.
For dry volume measures, the following are usually included in a metric spoon and cup set:
Spoons: 1, 2, 5, 15, (25) mL
Equivalent to 1/4. 1/2, 1 Tsp, 1 Tbs, 2 Tbs.
Cups: 50, 125, 250 mL
Equivalent to 1/4 cup (actually closer to 1/5 cup), 1/2 cup, 1 cup.
For liquid measure, the two sizes of measuring cups in our kitchen cupboard are a 250 mL (one cup) measure and a 500 mL (two cup) measure. The smaller one is marked in 25 mL increments, the larger in 50 mL increments. The 'English' scale on both is in 2 oz (1/4 cup) increments, with additional ticks at the 1/3 cup points. For most purposes, I suspect the same equivalents as for dry measure would work.
A further complication, though, is that many European recipes specify quantities in mass units (grams) rather than volumn units. from my 'outside the kitchen' perspective, conversion of English system volume to metric masses would seem to depend on the material being measured—a teaspoon of salt, for example, has far more mass than a teaspoon of pepper.
DISCLAIMER: While I can show you how to convert from one set of units to the other using a Lookup table, please do not rely on my choice of numbers/values for the pairings. I'm looking at this from an 'outside the kitchen' perspective, and the post has not been vetted by the chef of the household. The choice of values to list on the table is up to you. You may want to refer to the
Wikipedia article on Cooking weights and measures
With that in mind, here's an example of the use of a lookup table to convert from one unit to another.
The formula, entered in C2 and filled down through that column is:
=IFERROR(VLOOKUP(B,Lookup :: $A:$B,2,FALSE),"not found")
The IFERROR function serves as an error trap, producing the "not found" message where the lookup table does not contain the English amount listed in that row of the ingredients list. In this case, it caught the difference in spelling (s vs no s). Note that Lookup in not case sensitive (ingredient 5).
As written, a separate table should be used for the list of ingredients and quantities. The lookup table may be located on a separate sheet, and may serve several recipe's ingredients lists, provided those recipes and tables are all included in the same document.
Regards,
Barry
Regards,
Barry
