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Garden with Insight v1.0 Help: daily variable/state variable/parameter
This simulation has a daily time step, which means that calculations are carried out only once per
simulated day. The word "today" is used in the simulation to show you that a value was
calculated for the last day simulated. For example "Solar radiation today" means the total
amount of solar radiation making its way to the garden during the last simulated day. Daily values
change every day, as opposed to state variables and parameters. State variables simulate some
physical things that persist from one day to the next, such as soil pH,
and may or may not change every day (they simulate the state of something). Parameters never
change at all. Parameters can change how the simulation behaves by changing the calculation of
other variables, but they are never themselves changed.
As an example, you could think of your height as a state variable (it changes only slowly), what you eat
today as a daily variable (it changes every day), and your genetic tendency toward a particular height as a
parameter (it influences how tall you are, but you can't change it).
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