Page 57 - ExtendSim User Guide
P. 57

Building a Model 31
Working with block dialogs
In the label entry box beside the Help button, type in Rainfall. Labels can have a maximum of 31 characters, including spaces.
Adding label to the Lookup Table block
Block labeled “Rainfall”
On the Options tab, enter the following text in the column
labels box to give more meaningful headings to the table (be sure to include the semi- colon):
Month;Rainfall (inches)
Return to the Table tab
The table’s left column now specifies the month and the right column specifies the amount of expected rainfall in inches. At each step, ExtendSim will check the block’s table for a time in the first column that is less than or equal to the current simulation time and output the corre- sponding value (inches of rainfall) to its right. For instance, for the fourth month the block will output 1.9.
Click OK to close this block’s dialog.
Stream source
In this model, the Random Number block is used to specify a random distribution of water entering the reservoir from the stream. The distribution is a real number between 0 and 1, indi- cating that the stream will add between 0 and 1 inches of water to the reservoir’s level each month.
Open the Random Number block’s dialog.
By default the dialog’s parameters already have the
settings you want:
Distribution: Uniform Real (Default) Minimum: 0 (Default)
Maximum: 1 (Default)
Enter Stream in the label field next to the Help but- ton.
Click OK.
Random Number dialog settings

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