Bivariate Statistics

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Flow Statistics	General Statistics	Single Variable Histogram	Bivariate Statistics

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General Description

This model is used in Dynamic Simulation only.

The Bivariate Statistics model can be used to calculate and display statistical information about two variables and their correlation.

1. The bivariate statistics graphic can be displayed by holding down the shift key and left mouse clicking on the Bivariate Statistics graphical symbol.
2. From the menu, select "Graph" and place on the flowsheet.

Data Sections

The default sections and variable names are described in detail in the following tables. The default Bivariate Statistics access window consists of 2 sections. This number may increase or decrease, based on user configuration.

Summary of Data Sections

1. BivariateStats tab - Contains general information relating to the unit.
2. Info tab - Contains general settings for the unit and allows the user to include documentation about the unit and create Hyperlinks to external documents.

Bivariate Statistics Page

Unit Type: BivariateStats - The first tab page in the access window will have this name.

Tag (Long/Short)	Input / Calc	Description/Calculated Variables / Options
Tag	Display	This name tag may be modified with the change tag option.
Condition	Display	OK if no errors/warnings, otherwise lists errors/warnings.
ConditionCount	Display	The current number of errors/warnings. If condition is OK, returns 0.
GeneralDescription / GenDesc	Display	This is an automatically generated description for the unit. If the user has entered text in the 'EqpDesc' field on the Info tab (see below), this will be displayed here. If this field is blank, then SysCAD will display the UnitType or SubClass.
Requirements
On	Tick box	When ticked, the model will log data and perform calculations.
StatTag1	Input	The first tag which will be logged, Variable 1. This will be graphed on the x-axis and calculations performed on its values.
StatTag2	Input	The second tag which will be logged, Variable 2. This will graphed on the y-axis and calculations performed on its values.
Reset	Button	This will reset the calculations and graph.
Auto_Reset	Tick box	If ticked, the calculations and graph will be reset at the beginning of every model run.
Graph_x_Minimum / GraphMinx	Input	The minimum value to be shown on the x-axis of the graph. Any values lower than this will not be shown on the graph.
Graph_x_Maximum / GraphMaxx	Input	The maximum value to be shown on the x-axis of the graph. Any values higher than this will not be shown on the graph.
Graph_x_Minimum / GraphMiny	Input	The minimum value to be shown on the y-axis of the graph. Any values lower than this will not be shown on the graph.
Graph_y_Maximum / GraphMaxy	Input	The maximum value to be shown on the y-axis of the graph. Any values higher than this will not be shown on the graph.
Correlation / Corr	Calc	The calculated correlation between the two tags StatTag1 and StatTag2. A value of 1 means they are perfectly correlated.
Variable 1
Value1 / Val1	Calc	The current value of Variable 1 (StatTag1).
Average1 / Avg1	Calc	The average of the logged values of Variable 1 since the model was last reset.
StandardDeviation1 / StdDev1	Calc	The standard deviation of the logged values of Variable 1 since the model was last reset.
Minimum1 / Min1	Output	The minimum value of Variable 1 since the model was last reset.
Maximum1 / Max1	Output	The maximum value of Variable 1 since the model was last reset.
Variable 2
Value2 / Val2	Calc	The current value of Variable 2 (StatTag2).
Average2 / Avg2	Calc	The average of the logged values of Variable 2 since the model was last reset.
StandardDeviation2 / StdDev2	Calc	The standard deviation of the logged values of Variable 2 since the model was last reset.
Minimum2 / Min2	Output	The minimum value of Variable 2 since the model was last reset.
Maximum2 / Max2	Output	The maximum value of Variable 2 since the model was last reset.
Number_of_Records / N	Output	The number of pairs of values logged since the model was last reset.

Adding this Model to a Project

Add to Configuration File

Sort either by DLL or Group:

	DLL:	ControlDyn.dll	→	Units/Links	→	Statistics: Bivariate Statistics
or	Group:	General	→	Units/Links	→	Statistics: Bivariate Statistics

See Model Selection for more information on adding models to the configuration file.

Insert into Project Flowsheet

Insert Unit

→

Statistics

→

Bivariate Statistics

See Insert Unit for general information on inserting units.