software for corona virus modelling

This software fits data available corona for accumulated world infections to an empirical equations, and extrapolated the fitted equation

Software for Modelling of Corona Virus infections
This software uses published daily number of corona virus infections worldwide to predict future development of the outbreak. The daily infections data cover the period starting from January 22 2020 as day one until March 24 April 2021 These data are obtained from:
https://www.worldometers.info/coronavirus/coronavirus-cases/#total-cases
The data trend show interesting behavior. After the start the daily increase continued to grow relatively fast until it began to show some signature of leveling off at about day 30. This may reflect the beginning of the leveling of the disease in China. However, this trend is overshadowed by a new fast increase beginning at about day 40 reflecting the refreshed outbreak in Europe in general and Italy in particular. This trend is still on the increase.
In order to model such behavior empirically, one need to super impose two similar mathematical functions but with different parameters. These functions must have the following inherited properties
1- Slow start followed by fast increase
2- Saturation at some point
The function I use has the form
y=exp⁡[a_1 tanh⁡((x-a_2)/a_3 )+a_4+exp⁡[a_5 tanh⁡((x-a_6)/a_7 )
The seven parameters (a1 to a7) are free fitting parameters. The tangent hyperbolic function has the inherited saturation property, while the exponentiation enhances the fast increase property. The data are fitted to this equation using the matlab nonlinear fitting facility. The results are shown in figure (1). The experimental data are plotted as dots, the fitted equation as solid red, the fitted equation is extrapolated up to day 150. The main results are
1- The equation fits the data well enough
2- Leveling off of the infections is expected to start some tome around day 100 (This means the end of April or beginning of May)
3- Estimated total number of world infections may reach 450000

N.B The software can be updated daily by just adding the new daily total world infection cases to the variable Y in the program corona and running the program. It would be interesting to see how things change