A B C D E F G H I J K L M N
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3 RandNum
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5 Category: Simulation Modelling
6 Family: Monte Carlo
7 Arguments:
8 Meaning: Compute a semi random number
9 Description: This function generates a random number.  The number it generates is actually a semi-random number, because it comes from a pre-ordained sequence of random numbers from a seed.  The Business Functions menu, under Monte-Carlo, gives you the option to seed the generator.  If the generator is re-initialised time and again with the same seed, the identical set of random numbers will flow from the RandNum function.  In fact, because the sequence of numbers is determined in one go rather than each number dependent on the previous, you can even use PickRandom to choose what number you'd like from the sequence, if desired.  The repeatability from a specific seed means that your workbooks are repeatable.  Our experience of Monte-Carlo simulation work is that it really helps to have the random number sequence repeatable, for debugging your model and seeing changes in isolation.
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12        
13 #   0.3932     0.5116     0.3194     0.4193  
14 #   0.7212     0.2831     0.8822     0.4358    
15 #   0.1638     0.4311     0.3989     0.0868   Average of 40 Numbers:   0.4240
16 #   0.1937     0.9648     0.2631     0.4346    
17 #   0.4330     0.2089     0.2095     0.9053  
18 #   0.4518     0.9786     0.2811     0.8356  
19 #   0.0127     0.6901     0.1886     0.1468  
20 #   0.6816     0.3459     0.2547     0.0546  
21 #   0.3631     0.3774     0.5306     0.1768  
22 #   0.7174     0.2265     0.6804     0.3049  
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25 This function creates a semi-random number.
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27 The points to note are:
28 n  The function is 'volatile', that is, it will always recalculate when the worksheet or workbook recalculates,
29         not just if the workbook has changed.
30 n  The random numbers are semi-random, that is they proceed in a repeatable sequence for any given value of Seed.
31 n  Seed' provides a starting point for the random numbers, and is itself the first random number.  Seed is set as follows:
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33 - When Business Functions is first loaded, Seed is set to 3167 - no reason for this, any number from 0 to 32767 will do.
34 - Seed can be set as one of the input parameters to the Monte-Carlo when doing a simulation.
35 - It can also be set from the Business Functions menu
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