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Next: Hierarchical Grouping Proposal Up: Some Applications of Binary Previous: Replacing Random Groups Multiple Arrays in One HDU

  While a series of matrices can often be combined into a single primary data array by adding another dimension, to do so is not always possible. For example, consider an array that consists of a digital image accompanied by an array of quality flags, each of which corresponds to a pixel on the original image. If the data type of the flags differs from that of the image pixels, the flags cannot be combined into the primary data array. One way is to have the data array and flag arrays as separate image extensions. An alternative is to use binary tables. Each row would contain data for one image. One column would be a multidimensional array in floating point format, containing the image, and another would be a multidimensional array in integer format, containing the flags.