Operator`s manual

SECTION 10. PROCESSING INSTRUCTIONS
10-11
*** 61 INDIRECT INDEXED MOVE ***
FUNCTION
Moves input data from location X to location Y,
where X and Y are indirectly addressed. The
values of the location numbers X and Y are
stored in the locations specified by Parameters
1 and 2. The 21X looks in the locations
specified in the parameters to find the locations
to use as the source and destination of the data.
When used within a LOOP, a location parameter
can be specified as "indexed" (xxxx-), then the
actual Input location referenced is calculated by
adding the current index counter to the value in
the specified Input location.
PAR. DATA
NO. TYPE DESCRIPTION
01: 4 Input location in which Source
Input location is stored
02: 4 Input location in which Destination
input location is stored
*** 62 COVARIANCE/CORRELATION ***
FUNCTION
The special Covariance/Correlation Instruction
(CV/CR) for the 21X calculates: 1) means (M),
2) variances (V), 3) standard deviations (SD), 4)
covariances (CV), and 5) correlations (CR) for a
set of input values and stores the results in Input
Storage. The instruction requires the set of
input values to be located contiguously in Input
Storage. The user specifies the location of the
first value and how many total values exist. The
number of input values processed by each type
of calculation (means, variances, etc.) is
independently specified for each type. The
order of the input values determines which
inputs are processed for each type of
calculation.
The instruction does not conform to the 21X's
four instruction types. Data located in Input
Storage is processed, and the results returned
to Input Storage whenever an averaging period
is completed (Parameter 7) or the Output Flag is
set. The instruction controlling the Output Flag
must precede the CV/CR Instruction. The
reason the calculated results are returned to
Input Storage is to allow the user access for
additional processing before storing the values
in Final Storage. Sample Instruction 70 must be
used to transfer final results from Input to Final
Storage.
To accommodate cases where it is desirable to
calculate the statistical quantities over time
periods shorter than the Output Interval, an
averaging period shorter than the Output Interval
may be specified. The final values obtained at
the Output Interval are the properly weighted
average of the values calculated at the
subinterval averaging periods. This feature
allows the recording of statistical data over
longer time periods by removing the effect of
longer period frequencies in the input signals;
i.e., it provides a high pass filter. For example,
assume the variance of an input is desired. It is
determined that the averaging period should not
exceed 5 minutes due to variation in the mean
over longer time intervals. One approach is to
calculate and record the variance every 5
minutes. By specifying the subinterval
averaging period as 5 minutes and the Output
Interval as 1 hour, however, the average of the 5
minute variances are recorded every hour. The
averaging period is entered as the number of
input samples in Parameter 7 of the CV/CR
Instruction. The number of samples for a given
period is given by:
Number of Samples =
Averaging period in seconds
Table execution interval in seconds
PAR. DATA
NO. TYPE DESCRIPTION
01: 2 Number of input values located
sequentially in input memory
02: 2 Number of means desired
03: 2 Number of variances desired
04: 2 Number of standard deviations
desired
05: 2 Number of covariances desired
06: 2 Number of correlations desired
07: FP Number of input samples in
averaging period
08: 4 Input storage location of first value
in sequential input string
09: 4 First Input Storage location to
store string of final results
If the specified number of samples in the
averaging period (Parameter 7) exceeds the
actual number of samples occurring in the
Output Interval, the Output Interval becomes the
averaging period.