add_lines_X_SEIS.Rd
Add lines for the density of infected individuals for the SEIS model
add_lines_X_SEIS(time, XH, nStrata, clrs = c("darkblue", "darkred"), llty = 1)
time points for the observations
a list with the outputs of parse_Xorbits_SEIS
the number of population strata
a vector of colors
an integer (or integers) to set the `lty` for plotting