In v3.5.2 and earlier, the default for Line, Double Y, Double X, and Double XY plots is to show a Fixed # of markers, which is set to 5. To see more, choose Plot > Variable Settings and select All in the Show Markers pop-up menu. As of v3.6, this now defaults to All.
KaleidaGraph is a thoughtfully designed graphing and data analysis application for research scientists, as well as for those in business and engineering fields. It produces publication-quality graphs, and easily converts the most complex data into a functional display.