Page 720 - ExtendSim User Guide

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Math and Statistical Distributions
Blocks that represent functions
ExtendSim provides an extensive palette of tools for integrating mathematical equations and randomness in a model. You can even control the exact moment that calculations will take place. This chapter discusses:
• Blocks that provide mathematical functionality
• Using Equation blocks to create custom equations
• Incorporating randomness in models
• Selectingaprobabilitydistribution
• Determiningwheninputsshouldbeintegratedorsummed
☞ See also the How To chapter titled “Analysis” on page 641.
Blocks that represent functions
ExtendSim libraries are toolkits of blocks for quickly building a graphical representation of model logic. As shown below, some blocks have specific mathematical functionality and per- form calculations automatically based on settings in their dialogs. Other blocks provide even more flexibility and perform calculations based on equations you enter in their dialogs; they are discussed on “Equation-based blocks” on page 695.
☞ For information about blocks that perform statistical analysis, see “Blocks that calculate statis- tics” on page 642.
The following blocks may be used in any type of model to provide mathematical functionality based on dialog selections:
Decision (Value library)
Compares the value at one input to the value at another input and reports a result. For example, use this block to determine if one model value is greater than, less than, or equal to another value during the simulation run.
Integrate (Value library)
Provides different integration methods to integrate the input value over time. You can also set an initial value in the dialog.
Math (Value library)
Calculates a mathematical, financial, logical or trigonometry function depending on the option selected in its dialog. Set the block to add a number to its input value and output the result. Or have it calculate the exponent of the input value. Provides over 30 functions from a popup list.
Mean & Variance (Value library)
Calculates the mean, variance, and standard deviation of the input. You can set an initial value in the dialog and select options to calculate a moving average, use a specified confidence interval, collect interval statistics for a specified time period, and use time weighted statistics.
How To
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