The int_proj function can be called with just one parameter argument, in which case all the default arguments will be used. Simultaneous fits can be used given the first id and a list of otherids. Data set IDs can be integers or strings; in the latter case a string can denote useful information about the data (e.g., whether it is your source or background data set). The limits of the plot can be specified using the min and max keyword arguments. To quickly replot the cached arrays from a previous calculation, in the case of overplotting multiple int_proj plots in one window, the replot and overplot keyword arguments can be set.