binary format CEL binary format CEL binary format is a binary data format specification created by Affymetrix where values are stored in little-endian format. The CEL format stores the results of the intensity calculations on the pixel values of the DAT file. This includes an intensity value, standard deviation of the intensity, the number of pixels used to calculate the intensity value, a flag to indicate an outlier as calculated by the algorithm and a user defined flag indicating the feature should be excluded from future analysis. The file stores the previously stated data for each feature on the probe array. Allyson Lister It is unclear whether, originally, this format was intended to be the ASCII or binary version of the CEL format. As such, this class has been renamed as the binary format, and a new class created (CEL ASCII format) to make both options available. (22/05/2013) http://www.affymetrix.com/support/developer/powertools/changelog/gcos-agcc/cel.html, accessed 22 May 2013.