How to analyze analog output waveform in Modelsim
Yes, you can. On the Wave window, select your signals and right-click Under 'Format', select 'Analog' to see your signal as an analogue wave.

If you have a lot of data, you could write VHDL to write your values data into an output file in .CSV format (Comma-Separated Values). Then you could import that .CSV file into Excel and plot a graph from it.