How to calculate limits by contribution to a reference data by sample?Hello,
I am doing a stability study and want to set limits at +/- 20% of my result on day 1. I know how to add the limits to the graoh thanks to the help of another member of this community but now I will want to set up a formula so that this limit is calculated automatically taking into account the value on day 1 for each sample.
I wrote this formula for the upper limit but it doesn't work.
: Data [Row (),: Day == 1] * 1.2
I think I am using the index wrong.
I put in PJ the example table that I use with the results that I will want following the application of the formulas on the columns USL (value at Day 1 + 20%) and LSL (value at Day 1 - 20%) .
Does anyone have a solution?
thank you in advance
Data TableRe: Comment calculer des limits par apport à une donnée de référence par échantillon?Hi,
For this type of operations, I tend to use a simplified approach that relies on creating a new "Day 1" column with the formula below:
If (Row () == 1, :MEASURE, if (:TIME == "Day 1", :MEASURE, Lag (:DAY_1, 1))
Then it is a simpler procedure to calculate the USL and LSL as a reference for the other time points.
Does that make sense?
Best,
TS
Re: How to calculate limits by contribution to a reference data by sample?Hello,
thanks for your answer but sorry but I don't manage to do it.
I understand that you want to create a new column where I report Day 1 data for all timepoints. But then how do you create this column? I have lot of rows and cannot copy paste each row one by one. If your formulate is to create this row it doesn't work for me. What is you Day_1 variable? Is it the new row name or the name for the limits values?
Best,
Married
Re: Comment calculer des limits par apport à une donnée de référence par échantillon?Hi,
Sorry for the confusion. Here are the detailed steps to produce the desired result
- Sort your table by SAMPLE (first) and Day (Second)
- Add a new column named "DAY_1"
- Enter the formula below in the new column
If( Row() == 1,
:Data,
If( :Day == 1,
:Data,
Lag( :DAY_1, 1 )
)
)
The rest should be relatively easy but don't hesitate to contact me if you have problem creating the USL and LSL from the new DAY_1 column.
Best,
TS
