{"action":"closed","issue":{"url":"https://api.github.com/repos/ElOceanografo/StateSpace.jl/issues/13","repository_url":"https://api.github.com/repos/ElOceanografo/StateSpace.jl","labels_url":"https://api.github.com/repos/ElOceanografo/StateSpace.jl/issues/13/labels{/name}","comments_url":"https://api.github.com/repos/ElOceanografo/StateSpace.jl/issues/13/comments","events_url":"https://api.github.com/repos/ElOceanografo/StateSpace.jl/issues/13/events","html_url":"https://github.com/ElOceanografo/StateSpace.jl/issues/13","id":139055203,"number":13,"title":"Framework for Varying Time steps","user":{"login":"waTeim","id":5779395,"avatar_url":"https://avatars.githubusercontent.com/u/5779395?v=3","gravatar_id":"","url":"https://api.github.com/users/waTeim","html_url":"https://github.com/waTeim","followers_url":"https://api.github.com/users/waTeim/followers","following_url":"https://api.github.com/users/waTeim/following{/other_user}","gists_url":"https://api.github.com/users/waTeim/gists{/gist_id}","starred_url":"https://api.github.com/users/waTeim/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/waTeim/subscriptions","organizations_url":"https://api.github.com/users/waTeim/orgs","repos_url":"https://api.github.com/users/waTeim/repos","events_url":"https://api.github.com/users/waTeim/events{/privacy}","received_events_url":"https://api.github.com/users/waTeim/received_events","type":"User","site_admin":false},"labels":[],"state":"closed","locked":false,"assignee":null,"milestone":null,"comments":1,"created_at":"2016-03-07T18:31:58Z","updated_at":"2016-03-07T19:09:11Z","closed_at":"2016-03-07T19:09:11Z","body":"This is more of a question than an error.  I have an application where I want velocity combined with position similar to you [linear example](https://github.com/ElOceanografo/StateSpace.jl/blob/master/examples/LinearKalmanFilterControlInput_CanonBallExample.jl).  However, *delta t* is not a constant.  There is some information about what to do in this situation [in this SO question](http://stackoverflow.com/questions/25149165/variable-time-step-in-kalman-filter)  and [this research paper](https://www.ualberta.ca/~slshah/public_share/weihua/mr_kalman_fdi_rev.pdf) and a [MATLAB inplementation](http://www.mathworks.com/help/control/getstart/estimating-states-of-time-varying-systems-using-kalman-filters.html).  But it's unclear to me how to apply these things using StateSpace.  Can you suggest a path?"}}