I frequently use tools like Paraview, Octave/Matlab, R, and Maple to analyze Spice simulation results. While some of these tools can directly import Spice RAW files, most can’t or require extra components to do so. My solution is to just transform everything into CSV.

spiceRaw2CSV.rb

Convert RAW spice files to CSV.

spiceExportToCSV.rb

Convert Spice exported files to CSV.
By “exported” I mean files generated via ngspice’s wrdata or LTSpice’s menu [file]->[Export data as text]