How to get data from piwik in JS

how to get data from piwik in JS. Thank You!

Via HTTP-request and analytics API.
At the top of your PIWIK-site there is a link called API. There you find a list of all available methods with examples as well as some useful links.

Thank you bro! but please describe me more detail, how can i call for example piwik API method VisitTime.getByDayOfWeek from my site in javascript.

On JS side you have to use AJAX (XMLHttpRequests).
For the Piwik side please refer to the docs, guides and API-reference available online, which are very detailed. You can find them eg here:
http://piwik.org/docs/analytics-api/
http://developer.piwik.org/guides
http://developer.piwik.org/api-reference/reporting-api