{"action":"created","issue":{"url":"https://api.github.com/repos/wush978/FeatureHashing/issues/59","labels_url":"https://api.github.com/repos/wush978/FeatureHashing/issues/59/labels{/name}","comments_url":"https://api.github.com/repos/wush978/FeatureHashing/issues/59/comments","events_url":"https://api.github.com/repos/wush978/FeatureHashing/issues/59/events","html_url":"https://github.com/wush978/FeatureHashing/issues/59","id":61920050,"number":59,"title":"Size of the matrix in memory","user":{"login":"pommedeterresautee","id":1029874,"avatar_url":"https://avatars.githubusercontent.com/u/1029874?v=3","gravatar_id":"","url":"https://api.github.com/users/pommedeterresautee","html_url":"https://github.com/pommedeterresautee","followers_url":"https://api.github.com/users/pommedeterresautee/followers","following_url":"https://api.github.com/users/pommedeterresautee/following{/other_user}","gists_url":"https://api.github.com/users/pommedeterresautee/gists{/gist_id}","starred_url":"https://api.github.com/users/pommedeterresautee/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/pommedeterresautee/subscriptions","organizations_url":"https://api.github.com/users/pommedeterresautee/orgs","repos_url":"https://api.github.com/users/pommedeterresautee/repos","events_url":"https://api.github.com/users/pommedeterresautee/events{/privacy}","received_events_url":"https://api.github.com/users/pommedeterresautee/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":9,"created_at":"2015-03-15T23:26:33Z","updated_at":"2015-03-16T12:14:22Z","closed_at":null,"body":"There is something I am not understanding. \r\nWhen I hash a small dataset with a big space (like 2^25) the matrix is big in memory. But it is a sparse dcgMatrix. Why?\r\n\r\nIn the paper from J. Langford, it says that the sparsity preserved after hashing. Therefore, the very big matrix should be even more empty than the small one. And should not take more space in memory.\r\n\r\nWhat am I missing?\r\n\r\nKind regards,\r\nMichael"},"comment":{"url":"https://api.github.com/repos/wush978/FeatureHashing/issues/comments/81612824","html_url":"https://github.com/wush978/FeatureHashing/issues/59#issuecomment-81612824","issue_url":"https://api.github.com/repos/wush978/FeatureHashing/issues/59","id":81612824,"user":{"login":"wush978","id":1252618,"avatar_url":"https://avatars.githubusercontent.com/u/1252618?v=3","gravatar_id":"","url":"https://api.github.com/users/wush978","html_url":"https://github.com/wush978","followers_url":"https://api.github.com/users/wush978/followers","following_url":"https://api.github.com/users/wush978/following{/other_user}","gists_url":"https://api.github.com/users/wush978/gists{/gist_id}","starred_url":"https://api.github.com/users/wush978/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/wush978/subscriptions","organizations_url":"https://api.github.com/users/wush978/orgs","repos_url":"https://api.github.com/users/wush978/repos","events_url":"https://api.github.com/users/wush978/events{/privacy}","received_events_url":"https://api.github.com/users/wush978/received_events","type":"User","site_admin":false},"created_at":"2015-03-16T12:14:22Z","updated_at":"2015-03-16T12:14:22Z","body":"For the issues of vignette, I think we should discuss it in #60 . \r\n\r\nFor the space complexity, I think it could be written in the documentation of `hashed.model.matrix` or somewhere. How do you think?"}}