@jsaispas,
You can show just first 10 datapoints within the viewport by setting viewportMaximum property to 10 (when x-values are 1,2,3,…). If you are looking for showing top-10 (datapoints with highest y-values) to be shown, please take a look at this JSFiddle.
If you are still finding difficulty in achieving what you are looking for, kindly create JSFiddle with your use-case and share it with us so that we can look into the sample data & the chart-options being used, understand the scenario better and help you out.
—
Vishwas R
Team CanvasJS