HEIDENHAIN ND 2100G - Manual (Page 217)

ND 2100G GAGE-CHEK 217
2.4 F
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Dynamic average (Davg) and dynamic median (Dmd) functions
The dynamic average (davg) and dynamic median (dmd) functions
assign values to dimensions based on the average or median values
of dynamically sampled channels or dimensions. The sampled values
are assigned directly. Dynamic averages are useful when measuring
rough surfaces. Dynamic medians are useful when measuring in the
presence of noise.
ND 2100G channel inputs are sampled many times per second and
the system updates and retains the average and median values
encountered in the sampling process. Average and median values are
evaluated simultaneously during sampling. The number of samples
used to calculate the average or median is specified as an argument
by the user. Smaller numbers of samples have little impact on system
performance but result in rapidly changing averages and medians.
Larger numbers of samples result in more stable averages and
medians but slow system performance.
Dynamic average and median values can be calculated for any term or
collection of terms. Pressing the ENTER button stores the average
and median values.
To insert a davg or dmd function:
U Press the OTHER... soft key
U Press the DAVG or DMD dimension key
Dynamic average function.
Dynamic median function.
Davg function syntax
A = davg(Sampled value, sample size)
Assigns the average value of the samples. The minimum sample
size for averages is 2.
Dmd function syntax
A = dmd(Sampled value, sample size)
Assigns the median value of the samples. The minimum sample
size for medians is 3.
The sample size must be specified using a dimensionless
constant.
The RsetDyn function discussed on page 245 must be
used to clear existing samples before using the dmn and
dmx functions.
Due to the relatively low sample rates of the davg and dmd
functions, surfaces must be moved slowly during the
sampling process to insure that all points are evaluated.