Single Variable Histogram
Navigation: Main Page > Models > Statistical Models
Contents
General Description
This model is used in Dynamic Simulation only.
The Single Variable Histogram can be used to calculate and display statistical information about one variable.
The Histogram graphic can be displayed by holding down the shift key and left mouse clicking on the Single Variable Histogram graphical symbol. From the menu, select "Histogram" and place on the flowsheet. See example below:
Data Sections
The default sections and variable names are described in detail in the following tables. The default Single Variable Histogram access window consists of 2 sections. This number may increase or decrease, based on user configuration.
Summary of Data Sections
 SingleVarStats tab  Contains general information relating to the unit.
 Info tab  Contains general settings for the unit and allows the user to include documentation about the unit and create Hyperlinks to external documents.
Single Variable Histogram Page
Unit Type: SingleVarStats  The first tab page in the access window will have this name.
Symbol / Tag 
Input / Calc 
Description/Calculated Variables / Options 
On  Tick box  When ticked, the model will log data and perform calculations. 
StatTag  Input  The tag which will be logged, graphed and calculations performed on its values. 
Reset  Button  This will reset the calculations and histogram. 
Histogram_Minimum / HistoMin  Input  The minimum value to be shown on the histogram. Any values lower than this will be shown as a single bar on the histogram. 
Histogram_Maximum / HistoMax  Input  The maximum value to be shown on the histogram. Any values higher than this will be shown as a single bar on the histogram. 
Histogram_Buckets / HistoCount  Input  The number of intervals to be shown on the histogram. This excludes the bar for values which are under the specified minimum and the bar for values which are over the specified maximum. 
Graph_Units  List  The units to be used on the histogram. This list will change depending on the tag chosen for StatTag. 
Average / Avg  Calc  The average of the logged values of the specified tag since the model was last reset. 
Standard_Deviation / StdDev  Calc  The standard deviation of the logged values of the specified tag since the model was last reset. 
Minimum / Min  Output  The minimum value of the specified tag since the model was last reset. 
Maximum / Max  Output  The maximum value of the specified tag since the model was last reset. 
Number_Of_Records / N  Output  The number of values of the specified tag logged since the model was last reset. 
The following tags appear on the Histogram tab page.  
...  
RecordsSinceHistoReset / RSHR  Output  The number of values (records) of the specified tag logged since the model (histogram) was last reset. 
Buckets.[Bucket Number]...  
The buckets are simply the intervals on the histogram. The number of buckets = HistoCount + 2  
Minimum / Min  Output  The minimum value of the specified tag since the model was last reset for this bucket/interval. 
Maximum / Max  Output  The maximum value of the specified tag since the model was last reset for this bucket/interval. 
Count  Output  The number of values which fit into this bucket/interval. 
Note: If the value of the stattag is not a number (NAN) (shown as a "*"), then this will be counted as outside the range and put into the last bucket/interval.
Adding this Model to a Project
Insert into Configuration file
Sort either by DLL or Group.

DLL: 
ControlDyn.dll 
→ 
Units/Links 
→ 
Statistics: Single Variable Histogram 
or 
Group: 
General 
→ 
Units/Links 
→ 
Statistics: Single Variable Histogram 
See Project Configuration for more information on adding models to the configuration file.
Insert into Project

Insert Unit 
→ 
Statistics 
→ 
Single Variable Histogram 
See Insert Unit for general information on inserting units.