How can I reduce the number of PlotMarkers when I have many points in a ListLinePlot using the PlotTheme “Monochrome”?

Question

For example ListLinePlot[Range[10000], PlotTheme -> "Monochrome"] will show a marker for every point, how can I show a marker just every hundred points?

Answer 1

Taking a sample of the points and then working with Overlay or Show (e.g. mixing ListLinePlot, ListPlot) is a rather cumbersome solution. (Note, that just taking a sample of points, as the quickly accepted answer attempts, will not mark every hundredth point - it simply marks all points in a selection.)

There is a better way to achieve what the OP calls for (e.g. marking a selection of all points) by using Mesh:

SeedRandom["08.01.2019"];
points = RandomVariate[ UniformDistribution[], 50 ];
ListLinePlot[
    points,
    Mesh -> 30, (* setting this to 50-2 = 48 will give all points *)
    PlotTheme -> "Monochrome"
]

Playing around with the number of points used for Mesh gives the idea:

So for completeness' sake using Mesh the solution to the OP's problem is approximately:

ListLinePlot[Range[10000], Mesh -> (10000/100), PlotTheme -> "Monochrome"]

Answer 2

This will do it:

ListLinePlot[Range[10000][[1;;-1;;100]], PlotTheme -> "Monochrome"]

The [[1;;-1;;100]] part specification picks one element every 100 elements.