If the read is not identified as a control, then the 10th column (<control number>) is zero. If the read is identified as a control, the number is greater than zero, and the value specifies what type of control it is. The value is the decimal representation of a bit-wise encoding scheme. In that scheme bit 0 has a decimal value of 1, bit 1 a value of 2, bit 2 a value of 4, and so on.
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