[bika-dev] Sieving calculation

[Didier D. <did...@pi...>]

Hi everybody,

Sorry for my english, I'm a french speaker.

Is it possible to solve my problem in bika3?

In our laboratory, we have analysis on granulate (limestone) and we give 
results in 2 types; >5mm and <5mm

Attention: the order of the sieves is important, because it's like this 
we work.

First type: < 5mm:

sieves
	Weight in g
	Result in %
0.063mm
	3.17
	87.32
0.090 mm
	0.98
	96.08
0.100 mm
	0.61
	97.56
0.125 mm
	0.16
	99.36
0.200 mm
	0.01
	99.96
solde (rest)
	25.00
	


  * 25g is the weight of product we put on the first sieve (0.063 mm)
  * In this type of results, the calculation is ((25g - weight on each
    sieve)/25)*100
  * There is no result for the rest


The second type of results > 5mm is like this:

sieves
	Weight in kg
	Result in %
25.0 mm
	2.181
	56.467
20.0 mm
	1.62
	24.132
12.50 mm
	1.084
	2.495
7.10 mm
	0.107
	0.359
solde (rest)
	0.018
	


In this type of results, the calculation is like this; for example at 
12.50mm:

  * we calculate the total weight: 5.01 kg
  * at 12.50 mm the result is: ((5.01 - (1.084+1.62+2.181)/5.01))*100
  * it's the same for each sieve and there is no result for the rest

Actually, in our software, we say that for this equipment we use this 
type of calculation

Best regards

Didier Desplanque