A collection of tools for fitting several general-purpose linear and nonlinear models for COVID-19 epidemiological data. The longitudinal data is obtained from the John Hopkins database (source: https://github.com/CSSEGISandData/COVID-19) and consists of: number of active cases, number of confirmed, number of fatalities, number of recovered cases. The analysis is possible for any particular country listed in the database, or for the world data as a whole. The models implemented include linear, exponential, logistic, Gompertz, fifth-degree polynomial, Gaussians and Fourier functions. The three models of the Bertalanffy class (exponential, proper logistic and Gompertz) afford a reasonable balance between reduced model complexity and goodness of fit. We implement data/model visualization in linear and logarithmic scales, for easy model comparisons.
Lorand Gabriel Parajdi and Ioan Stefan Haplea (2020). COVID19 Data Fitting with Linear and Nonlinear Regression (https://www.mathworks.com/matlabcentral/fileexchange/75016-covid19-data-fitting-with-linear-and-nonlinear-regression), MATLAB Central File Exchange. Retrieved April 15, 2020.
Thank you for the interest in our Matlab package. We were unable to replicate the error you mentioned, but we do not have access to Matlab 2020. We tested the package on v2016a and v2019a only. We have rewritten the functions that fetch and process the data from the database. We avoided the reshape() function which caused the error and hopefully made the code more future-proof.
We would be very grateful If you could test on your platform the new functions and give us feedback.
With Matlab 2020a, I'm getting an error in all of the *.mlx files when calling reshape
Error using reshape
Number of elements must not change. Use  as one of the size inputs to automatically calculate the appropriate size for that dimension.
Error in get_global (line 14)
m = reshape(tn, lin, col);
changed my project website
improved functions for data parsing