{"action":"created","issue":{"url":"https://api.github.com/repos/mne-tools/mne-python/issues/1766","labels_url":"https://api.github.com/repos/mne-tools/mne-python/issues/1766/labels{/name}","comments_url":"https://api.github.com/repos/mne-tools/mne-python/issues/1766/comments","events_url":"https://api.github.com/repos/mne-tools/mne-python/issues/1766/events","html_url":"https://github.com/mne-tools/mne-python/issues/1766","id":55774132,"number":1766,"title":"Preload subset of channels or channel types from raw.fif","user":{"login":"haribharadwaj","id":5589178,"avatar_url":"https://avatars.githubusercontent.com/u/5589178?v=3","gravatar_id":"","url":"https://api.github.com/users/haribharadwaj","html_url":"https://github.com/haribharadwaj","followers_url":"https://api.github.com/users/haribharadwaj/followers","following_url":"https://api.github.com/users/haribharadwaj/following{/other_user}","gists_url":"https://api.github.com/users/haribharadwaj/gists{/gist_id}","starred_url":"https://api.github.com/users/haribharadwaj/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/haribharadwaj/subscriptions","organizations_url":"https://api.github.com/users/haribharadwaj/orgs","repos_url":"https://api.github.com/users/haribharadwaj/repos","events_url":"https://api.github.com/users/haribharadwaj/events{/privacy}","received_events_url":"https://api.github.com/users/haribharadwaj/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":13,"created_at":"2015-01-28T15:56:10Z","updated_at":"2015-01-28T21:54:38Z","closed_at":null,"body":"I have simultaneous MEG/EEG data sampled at 5 kHz (because I'm also recording brainstem activity) and it would nice to be able to preload say only EEG or only subsets of channels etc. and do analysis/eye-balling..  There are probably other good use cases for this too.. \r\n\r\nI can see this being possible quickly in a few different ways:\r\n(1) Add kwargs like eeg=True, meg=False etc. to pick only certain channel types..\r\n(2) Take channel names (as opposed to indices) list for a pickNames argument.. \r\n(3) Add a regular picks argument and then the user does two steps... (i) load with preload=False and determine picks from the info and then (ii) re-run the file read with preload=True and picks=picks\r\n\r\nThoughts?"},"comment":{"url":"https://api.github.com/repos/mne-tools/mne-python/issues/comments/71924585","html_url":"https://github.com/mne-tools/mne-python/issues/1766#issuecomment-71924585","issue_url":"https://api.github.com/repos/mne-tools/mne-python/issues/1766","id":71924585,"user":{"login":"agramfort","id":161052,"avatar_url":"https://avatars.githubusercontent.com/u/161052?v=3","gravatar_id":"","url":"https://api.github.com/users/agramfort","html_url":"https://github.com/agramfort","followers_url":"https://api.github.com/users/agramfort/followers","following_url":"https://api.github.com/users/agramfort/following{/other_user}","gists_url":"https://api.github.com/users/agramfort/gists{/gist_id}","starred_url":"https://api.github.com/users/agramfort/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/agramfort/subscriptions","organizations_url":"https://api.github.com/users/agramfort/orgs","repos_url":"https://api.github.com/users/agramfort/repos","events_url":"https://api.github.com/users/agramfort/events{/privacy}","received_events_url":"https://api.github.com/users/agramfort/received_events","type":"User","site_admin":false},"created_at":"2015-01-28T21:54:38Z","updated_at":"2015-01-28T21:54:38Z","body":"I would do:\n\nraw = mne.io.Raw(...)\npicks = mne.pick_types(raw.info, ...)\nraw.preload_data(picks=picks)\n\nand no later possibility to load other channels"}}