Personally, I have found the messages of support from scientists everywhere to be truly heartfelt, and I would like to highlight some of the community initiatives I’ve seen here: Replacing these calculations with a fitted distribution can have a marked effect on model size and speed.We also want to use our platform to highlight the response from the scientific community. fitting first or second order non-parametric distributions to data, constructing Bayesian posterior distributions, and Bootstrap analysis). Sometimes large data sets or calculation arrays are used to construct distributions (e.g. It is better to do the analysis outside the spreadsheet, and copy across the results Maintaining large data sets in your model will increase the file size. Using Crystal Ball reporting functions (as for example, using CB.GetForeStatFN( ) to automatically produce statistics after a simulation) will greatly increase the size of the model and slow it down Megaformulae reduce the file size considerably Try to limit the use of other applications by either closing or minimizing them.įinally, if you really put a lot of value on simulation speed, you can either buy CB Turbo or increase your system's RAM. This does have the disadvantage, however, of being more laborious to maintain when more data become available. Run Bootstrap analyzes and Bayesian distribution calculations in a separate spreadsheet when you are estimating uncorrelated parameters, fit the results using Crystal Ball's distribution fitting tool, and if the fit is good use just the fitted distributions in your simulation model.The sampling methods take the same time to run, however, so it makes sense to use Latin Hypercube sampling for simulation runs Īvoid using Crystal Ball's reporting functions, unless absolutely necessary Latin Hypercube sampling gets to the stable output quicker than Monte Carlo sampling., but the effect gets quickly lost the more significant distributions there are in the model, particularly if the model is not just adding and/or subtracting distributions. By default the Burst Model Option is on.Īvoid using Crystal Ball's Custom Distribution distribution with a large array if possible as they take much longer to generate values than other distributions Increase the burst mode by selecting Run, then Run Preferences, and then Speed. Suppress forecast window during simulations In the Run Preferences click on Speed dialog and select the following: Keep the simulation model in one workbook. Use megaformulae (with caution) as they run about twice as fast as intermediary calculations, and ten times as fast as VBA calculations Ĭustom Excel functions run more slowly than built-in functions but speed up model building and model reliability Making Excel run fasterĪvoid array functions as they are slow to calculate, although faster than an equivalent VBA function We'll look at a few hints for making Excel run faster, then making Crystal Ball run faster, and then making a model that gets the answer faster. It requires the least amount of assumptions andĬrystal Ball is an add-in to Excel and, although it is well integrated into Excel, it will inevitably suffer somewhat in performance because of the interface.
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