#acl ChrisSeidel:read,write,delete,revert All:read = MAT (Model-based Analysis of Tiling-array) = Requires Affy CEL files to be in a particular format. Type 4 binary files will not work. If you get an error message such as: 'not a valide cel file ' By default Command Console exports CEL files in type 4 format. To convert them into the correct format for MAT, use affy power tools. There's a program called: apt-cel-convert which will do the trick. It interconverts the following types: * text: GCOS Text file format (version 3) * xda: GCOS XDA binary file format (version 4) * agcc: AGCC binary format For example, from a linux command line: {{{ apt-cel-convert -f text -o CELv3 *.CEL }}} The -o option specifies the output directory. I'm not sure how to query the files to see what type they are.