Agilent Technologies 1670E Series, User Manual

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System Performance Analysis (SPA) Software
System Performance Analysis Software
State Histogram mode
State Histogram mode displays relative activity of ranges of a specified
label. The ranges can also be compared to activity on the rest of the
label not defined in the ranges. Data qualification is possible with State
Histogram, so data can be filtered during acquisition.
Data sampling and sorting. When Run is pressed, all input channels
defined in the Format Specification are sampled. Once acquired, each
sample in the acquisition is compared to each defined range. If the
sample value is inclusively within the range and if the range is on, the
count for that range is incremented, then the State Histogram display
is updated. The acquisition is repeated until Stop is pressed or until a
display variable is changed.
The histogram is displayed on a percentage scale, and each bar
represents the fraction of all samples in that range. For example, if a
bar reaches the 40% value on the display, then the range for that bar
contains 40% of all the samples displayed. If the total percentages of all
bars equals greater than 100%, then ranges have been overlapped and
data has been counted twice.
State Histogram vs. State Overview. State Histogram is similar to
State Overview, but there are key differences between the two modes.
State Overview shows relative distribution of activity over a single
contiguous range of a label. State Histogram also allows several non-
contiguous ranges of a label to be defined.
State Overview requires minimal setup, and provides a quick overview
of system activity. State Histogram requires more setup, but provides
greater resolution and measurement flexibility.