Try this:

> input <- read.table(text = "date time BG test
+ 4/3/13 19:20    105     Aviva-491350
+ 4/4/13 21:03    74      Aviva-491350
+ 4/6/13 17:40    81      Aviva-491640
+ 4/6/13 17:40    82      Aviva-491350
+ 4/6/13 22:48    106     Aviva-491640
+ 4/6/13 22:48    102     Aviva-491350
+ 4/7/13 5:32     87      Aviva-491350
+ 4/7/13 5:32     103     Aviva-491640", as.is = TRUE, header = TRUE)
> # set limits
> input$High <- ifelse(input$BG >= 100
+                 , input$BG * 1.15
+                 , input$BG + 15
+                 )
> input$Low <- ifelse(input$BG >= 100
+                 , input$BG * 0.85
+                 , input$BG - 15
+                 )
> input
    date  time  BG         test   High   Low
1 4/3/13 19:20 105 Aviva-491350 120.75 89.25
2 4/4/13 21:03  74 Aviva-491350  89.00 59.00
3 4/6/13 17:40  81 Aviva-491640  96.00 66.00
4 4/6/13 17:40  82 Aviva-491350  97.00 67.00
5 4/6/13 22:48 106 Aviva-491640 121.90 90.10
6 4/6/13 22:48 102 Aviva-491350 117.30 86.70
7 4/7/13  5:32  87 Aviva-491350 102.00 72.00
8 4/7/13  5:32 103 Aviva-491640 118.45 87.55
>



On Tue, May 7, 2013 at 10:02 AM, Neotropical bat risk assessments <
neotropical.bats@gmail.com> wrote:

> Hi all,
>
> I am trying to set up logical function(s) to deal with two adjustments
> to a blood glucose value.
> I have been dinking around in Excel and assume this will be much easier
> in R.
>
> DF is date-time, BG value in mg/dL,test strip
> 4/3/13 19:20    105     Aviva-491350
> 4/4/13 21:03    74      Aviva-491350
> 4/6/13 17:40    81      Aviva-491640
> 4/6/13 17:40    82      Aviva-491350
> 4/6/13 22:48    106     Aviva-491640
> 4/6/13 22:48    102     Aviva-491350
> 4/7/13 5:32     87      Aviva-491350
> 4/7/13 5:32     103     Aviva-491640
>
>
> What I need are the high and low ranges based on "acceptable" standards
> of the measured values.
>
> The logical expressions need to be
> IF BG =>100 then "High limit" would = (BG+(BG*.15))
> IF BG =>100 then "Low limit" would = (BG-(BG*.15))
> and
> IF BG <100 then "High limit" would = (BG+15)
> IF BG <100 then "Low limit" would = (BG-15)
>
> The standards are written as: 95% of the individual glucose results
> shall fall within ą15 mg/dL of the reference results at glucose
> concentrations less than 100 mg/dL and within ą15% at glucose
> concentrations greater than or equal to 100 mg/dL.
>
> Then I need to plot the measured value and also show the high & low
> "acceptable" values.
>
> Thanks for any who respond.
>
> Bruce
>
>
> --
> Bruce W. Miller, PhD.
> Neotropical bat risk assessments
>
> If we lose the bats, we may lose much of the tropical vegetation and the
> lungs of the planet
>
> Using acoustic sampling to map species distributions for >15 years.
>
> Providing Interactive identification keys to the vocal signatures of New
> World Bats
>
> For various project details see:
>
> https://sites.google.com/site/batsoundservices/
>
>
>         [[alternative HTML version deleted]]
>
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
>


-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.

	[[alternative HTML version deleted]]

