Test controller, histogram page

Histogram

This page shows one or more histograms of the logged/table values. It is possible to select number of bins.

Contents
    What is on the screen
    Histograms
    Range
    Scale type
    Resolution
    Save chart
    Curves
Main page



What is on the screen

Areas

In the above picture I have labelled the different areas of this page, in the following I will go more into details about each area.



Histograms

HistogramHistogram

The histogram shows the distribution of values, either as a count for each bar or as a percent of total data for each bar. The data used can be the full amount of data or a range of data.

Hist1

Hist2

Hist3

It is possible to show one, two or three histograms at a time.

The scale at the bottom of the histograms is defined on the "Scales for chart" and is the same as is used for a chart.



Range

Range

The range fields are used to limit the data used for the histogram, they list the first and the last sample to include. This can be selected on the chart page and copied to this page, but can also be entered manually.
There are a few options when entering values manually: When using the - prefix in the first sample the histogram will "roll" when data is updated, i.e. it is possible to view the last x samples all the time.



Scale type

ShowInPercent

Select between count and percent scale, the actual count and percent will often be smaller when a high amount of bins are used.



Resolution

Bins

This defines how many bars the bars the histograms is using, it can be from 5 to 1000 bins. It is best to keep the number of bins below the actual resolution.

LowRes
HighRes

Above is a very low resolution and a high resolution histogram.




Save chart

Save

It is possible to save the shown histograms as a png file. All shown histograms is saved as one png file. The screen resolution and save resolution is not related.

Save2

When pressing "Save" a save dialog will be shown where it is possible to select resolution of the saved png file.
The available resolutions are defined on the configuration page.



Curves

Curves

Measured values from all devices are listed here and it is possible to select what values to show as curves. Digital channels will not be included.