Casual Introduction to Numerical Methods – spring-mass-damper system model – part#5

22/02/2011

In this tutorial, most of the calculations for the numerical simulation a SMD (spring-mas-damper) system will be consolidated into a single formula, the coordinate formula. In this case, in order to calculate the coordinate at the end of a any time step, we will need just the coordinates from the previous two time steps and of course the input parameters (constants). These input parameters are: mass, damping ratio, spring constant and time…

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2D Projectile Motion Tutorial #7

20/02/2011

In the this tutorial, after we got most of the trajectory calculation concentrated in just two columns, we will write a custom VBA function (dual output) to replace the spreadsheet computations used. This process of  starting with very simple models, then refining the calculations and then learning how to write custom functions for those calculations will be extremely useful later for developing more complex models.

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2D Projectile Motion Tutorial #6

19/02/2011

This tutorial simplifies the previous model and manages to describe the (x,y) flight coordinates using just two formulas placed on columns D and E. A custom VBA trajectory function will be introduced in the next section which preserves the effects of gravity and aerodynamic drag.

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Near-Exponential VBA Conversion

18/02/2011

The macro in this tutorial creates a near exponential variable conversion to be used for very large dynamic range input data entry . If for instance, we have to adjust a parameter from 1 to 1 million we can either make a spin button which can go from 1 to 1 million in unity steps (which would take for ever), or implement an exponential scheme. We would like an exponential series of powers of…

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