{"action":"created","issue":{"url":"https://api.github.com/repos/pydata/pandas/issues/10730","labels_url":"https://api.github.com/repos/pydata/pandas/issues/10730/labels{/name}","comments_url":"https://api.github.com/repos/pydata/pandas/issues/10730/comments","events_url":"https://api.github.com/repos/pydata/pandas/issues/10730/events","html_url":"https://github.com/pydata/pandas/issues/10730","id":98687322,"number":10730,"title":"Add inplace option to DataFrame.update()","user":{"login":"dov","id":338235,"avatar_url":"https://avatars.githubusercontent.com/u/338235?v=3","gravatar_id":"","url":"https://api.github.com/users/dov","html_url":"https://github.com/dov","followers_url":"https://api.github.com/users/dov/followers","following_url":"https://api.github.com/users/dov/following{/other_user}","gists_url":"https://api.github.com/users/dov/gists{/gist_id}","starred_url":"https://api.github.com/users/dov/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/dov/subscriptions","organizations_url":"https://api.github.com/users/dov/orgs","repos_url":"https://api.github.com/users/dov/repos","events_url":"https://api.github.com/users/dov/events{/privacy}","received_events_url":"https://api.github.com/users/dov/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/pydata/pandas/labels/API%20Design","name":"API Design","color":"AD7FA8"},{"url":"https://api.github.com/repos/pydata/pandas/labels/Indexing","name":"Indexing","color":"0b02e1"},{"url":"https://api.github.com/repos/pydata/pandas/labels/Missing-data","name":"Missing-data","color":"d7e102"},{"url":"https://api.github.com/repos/pydata/pandas/labels/Needs%20Discussion","name":"Needs Discussion","color":"207de5"}],"state":"open","locked":false,"assignee":null,"milestone":{"url":"https://api.github.com/repos/pydata/pandas/milestones/32","html_url":"https://github.com/pydata/pandas/milestones/Next%20Major%20Release","labels_url":"https://api.github.com/repos/pydata/pandas/milestones/32/labels","id":933188,"number":32,"title":"Next Major Release","description":"after 0.16.1 of course","creator":{"login":"jreback","id":953992,"avatar_url":"https://avatars.githubusercontent.com/u/953992?v=3","gravatar_id":"","url":"https://api.github.com/users/jreback","html_url":"https://github.com/jreback","followers_url":"https://api.github.com/users/jreback/followers","following_url":"https://api.github.com/users/jreback/following{/other_user}","gists_url":"https://api.github.com/users/jreback/gists{/gist_id}","starred_url":"https://api.github.com/users/jreback/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/jreback/subscriptions","organizations_url":"https://api.github.com/users/jreback/orgs","repos_url":"https://api.github.com/users/jreback/repos","events_url":"https://api.github.com/users/jreback/events{/privacy}","received_events_url":"https://api.github.com/users/jreback/received_events","type":"User","site_admin":false},"open_issues":809,"closed_issues":61,"state":"open","created_at":"2015-01-13T10:53:19Z","updated_at":"2015-08-03T10:39:28Z","due_on":"2015-11-30T05:00:00Z","closed_at":null},"comments":2,"created_at":"2015-08-03T07:28:59Z","updated_at":"2015-08-03T11:02:29Z","closed_at":null,"body":"Currently `DataFrame.update()` modifies the dataframe in place. I feel this is not symmetric to how most other methods work, e.g. `set_index()`, that returns a new `DataFrame`. It is probably too late to change this default behavior (isi it?), but if at the very least an `inplace` option was added (with default value `True` to support the current behaviour), it will be easier to chain a sequence of operators that includes `update()`."},"comment":{"url":"https://api.github.com/repos/pydata/pandas/issues/comments/127195660","html_url":"https://github.com/pydata/pandas/issues/10730#issuecomment-127195660","issue_url":"https://api.github.com/repos/pydata/pandas/issues/10730","id":127195660,"user":{"login":"dov","id":338235,"avatar_url":"https://avatars.githubusercontent.com/u/338235?v=3","gravatar_id":"","url":"https://api.github.com/users/dov","html_url":"https://github.com/dov","followers_url":"https://api.github.com/users/dov/followers","following_url":"https://api.github.com/users/dov/following{/other_user}","gists_url":"https://api.github.com/users/dov/gists{/gist_id}","starred_url":"https://api.github.com/users/dov/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/dov/subscriptions","organizations_url":"https://api.github.com/users/dov/orgs","repos_url":"https://api.github.com/users/dov/repos","events_url":"https://api.github.com/users/dov/events{/privacy}","received_events_url":"https://api.github.com/users/dov/received_events","type":"User","site_admin":false},"created_at":"2015-08-03T11:02:29Z","updated_at":"2015-08-03T11:02:29Z","body":"I first encountered update as an answer to my stackoverflow question:\r\n\r\nhttp://stackoverflow.com/questions/31769754/looking-up-multiple-values-from-a-pandas-dataframe/31779537#31779537\r\n\r\nregarding how to a \"parallell lookup\" from all rows of one DataFrame by the values of another DataFrame.\r\n\r\nIn that example it might be useful to directly after the call to update() e.g. write the resulting dataframe to a csv file.\r\n"}}