Spirit flow-x, Справочник по функциям

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Flow-X─ Function Reference
Flow-X General functions - fxInterpolationCurve
fxInterpolationCurve
This function calculates the output value from a set of reference points and the actual input value. The
function can take an arbitrary number of reference points.
The function is typically used for applying a calibration curve to a K factor or a meter factor (liquid) or a
meter error curve (gas).
Besides of the 1st calibration point (which is always used) the function will only use the calibration
points (starting from the 2nd point) for which the x value is greater than the previous x value. All
further points will be ignored.
Function inputs Remark EU SW tag Range Default
Name Optional tag name, tag
description and tag group
Input value Reference to the cell containing
the actual input value (e.g. flow
rate or pulse frequency)
Reference values Array of reference values,
assuming the following
sequence:
Point 1 - Input value
Point 1 - Output value
Point 2 - Input value
Point 2 - Output value
etc....
The array must contain an even
number of values with the input
values in ascending order.
So it is required that Input 1 <
Input 2 < Input 3 etc.
However, when an input value
equals 0, then the function will
not use this point and all
subsequent points of the array.
REFVAL
Extrapolation
mode Determines whether or not
extrapolation must be applied
when the input value is outside
the linearization curve. When
disabled either the first or last
output value will be used.
0: Disabled
1: Enabled EXPMODE
Function outputs Remark EU SW tag Alarm Fallback
Output value Interpolated value Same as
input
'Output
reference
1' VAL 0
Date/time Latest modification date and
time of the any of the
reference point values DTTM
Out of range Input value is outside the
range that is covered by the
reference values OOR