Hi I am currently using the marray* Bioconductor packages to analyse my data. My data, in GenePix format, has been read successfully into marrayRaw classes. I now want to be able to subset my data - for example, I may want to calcualte the co-efficient of variance, or some other statistic there isn't an in-built method for, for each print tip; or each grid row; or each grid column. My planned method for doing this was to use the subset() function in some way, but I can't figure out how to access grid location details for each spot through the marrayRaw class - although I know it must be possible as lots of other functions, for example in marrayPlots, can slice marrayRaw objects up and draw things like print-top Loess lines. Thanks in advance for your help Mick

Hi Michael, If data is a marrayRaw object, use maPrintTip(data) to obtain print-tip information For other Grid location details, use: maGridRow(data), maGridCol(data), maSpotRow(data), maSpotCol(data). You should be able to subset a marrayRaw object the same way you subset matrix. E.g. data[maPrintTip(data) == 1,] will produce a marrayRaw object consists of data from print-tip 1. Hope this helps. Jean On Wed, 30 Jul 2003, michael watson (IAH-C) wrote: > Hi > > I am currently using the marray* Bioconductor packages to analyse my > data. My data, in GenePix format, has been read successfully into > marrayRaw classes. > > I now want to be able to subset my data - for example, I may want to > calcualte the co-efficient of variance, or some other statistic there > isn't an in-built method for, for each print tip; or each grid row; or > each grid column. My planned method for doing this was to use the > subset() function in some way, but I can't figure out how to access > grid location details for each spot through the marrayRaw class - > although I know it must be possible as lots of other functions, for > example in marrayPlots, can slice marrayRaw objects up and draw things > like print-top Loess lines. > > Thanks in advance for your help > > Mick > > _______________________________________________ > Bioconductor mailing list > Bioconductor@stat.math.ethz.ch > https://www.stat.math.ethz.ch/mailman/listinfo/bioconductor >