DaqErrFilter

class DaqErrFilter : public Pipe

This class simulates DAQ errors

Inheritance:

Public Methods
DaqErrFilter(const char* subtype): Daq error constructor.
~DaqErrFilter(void): Daq error destructor
std::string getTypeString(void) const: Return a string containing a list of error tyeps to be simulated
bool selectType(const std::string& s): Enable simulation of the specified error type
void setAvgWidth(double avgWid): Specify an average number of errors to be generated in a cluster of LSB errors
void setClusterWidth(long wid): Specify a fixed number of errors in a cluster
void setSubTypes(const std::string& s): Set the error tyopes to be simulated by this filter

Documentation

This class simulates DAQ errors. At present the error types included are:

Word swapping: during S1 several 16-bit word variables had the order each sample pair swapped. This mode operates only on 2-byte data time series.
LSB errors: errors occurred randomly in the Least Significant Byte (LSB) of 16-byte data transfers during science runs S1 - S3. The simulation code generates errors by jamming 0xff into the low order byte of random words. Fixed or random width clusters are generated at random intervals as specified by the setClusterWidth, setAvgWidth and setErrRate methods. The cluster start time is calculated by generating a random time offset from an exponential distribution with average time as specified by setRate. The time is adjusted to the previous 1/16th second boundary. If an average cluster width was specified, a random cluster width is generated from a Poisson distribution with the specified average. If the average with is zero, the specified constant cluster width is used. If a width specified or generated to be zero, no cluster is generated at the calculated start time.
The types of errors to be simulated are set by either the constructor argument or by the setSubTypes method. The type string is a comma separated list of error types with one or more of "swap" or "lsb".