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CSC8309 -- Gene Expression and Proteomics

Affy Quality Metrics

Next, we want to try an analyse a set of quality metrics for affy chips.

act

Download this file first.

Evaluate this code.

library( 'simpleaffy' )

## TODO this section is broken

## # Load (source in) function for quality control metrics revised
## # by W. Gregory Alvord and Octavio Quinones to work# with
## # soybeancdf
source('soybean.mod.qc.affy.r')

## # Execute soybean.mod.qc.affy() on object soy.ab
##soy.ab.qc <- soybean.mod.qc.affy(soy.ab)

## # Assign qc metrics to objects
## avbg.soy.ab.qc <- avbg(soy.ab.qc)
## minbg.soy.ab.qc <- minbg(soy.ab.qc)
## maxbg.soy.ab.qc <- maxbg(soy.ab.qc)
## sfs.soy.ab.qc <- sfs(soy.ab.qc)
## percent.present.soy.ab.qc <- percent.present(soy.ab.qc)

## # Display objects (here, rounded to 2 decimal places)
## round(minbg.soy.ab.qc ,2)
## round(maxbg.soy.ab.qc ,2)
## round(avbg.soy.ab.qc ,2)
## round(sfs.soy.ab.qc ,2)
## round(percent.present.soy.ab.qc,2)


(Complete File)(Rout)

Here we find one of the interesting things with working with cutting-edge, research software. It often does not work. In this case, there appears to have been a change between one version of bioconductor and the next; at least this is what the paper authors have told us 1.

quest
  1. Have a play with the code (uncommenting it, of course). Maybe bioconductor will have been fixed.
  2. If you really need to get this working, what would you do next?

1. Not that we doubt them, but it does nicely shift the blame on to someone else.


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