Flow CSV Editor is a light-weight tool for viewing, plotting and editing time series data files in CSV format. It's designed to be extremely quick and easy to use. It opens any valid CSV files immediately without any dialogs or complicated commands, and within seconds you'll be viewing, analyzing and editing the data of interest.
Flow was originally written with the signal processing engineer in mind. It is optimized for timed data such as measurement logs and sensor data files, but it's also useful for viewing and editing large machine learning data sets as well as for other applications where numeric data is involved. The data is visualized as line plots, and zooming, scrolling and rearranging the plots is fast and efficient, also on large data sets.
A free version without the editing and saving capabilities, Flow CSV Viewer, is available.