Linq: get part of resultset based on an interval

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Hi Folks,

I am writing an ASP.NET website which show global coordinates/geolocation on a google map.
Below that map I want to show a graph which displays some values that belong to that GeoLocation. Since it handles hundreds of thousands (it is a GMAP polyline with additional data. That additional data should show up in a graph) of points it is pretty impossible to create a graph for that (limit 32000 records).
How can I create a result set that holds any nth row from the full c# datatable
Can a linq query help me out to have a maximum of 10,000 rows from the original 150,000 rows. So a skip interval of 15 rows should do the trick.
In the resultset row 1, 16, 31.... and so should be set.

What I have tried:

I have Googled to see if that is possible but skip in linq only moves the pointer to a given row and the remainder of that set is then returned (150,000 - 15 is not want I want)

Posted 13-Oct-16 21:58pm

Herman<T>.Instance

Updated 13-Oct-16 22:58pm

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Midi_Mick · Accepted Answer · 2016-10-13T22:58:00

Solution 1

You can use the IEnumerable<T>.Where(Func<T, int, bool>) extension:

results = rows.Where((r,i)=>i % 15 == 0);

Posted 13-Oct-16 22:58pm

Midi_Mick

Comments

Midi_Mick 14-Oct-16 5:00am

or, for a faster result, every 16th element could be done with a bitwise operator rather than the modulus operator i.e. (i & 15) == 0

Herman<T>.Instance 14-Oct-16 5:29am

you're a legend!

Maciej Los 14-Oct-16 16:57pm

5ed!