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+[](https://datalad.org)
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+
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+## DataLad datasets and how to use them
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+
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+This repository is a [DataLad](https://www.datalad.org/) dataset. It provides
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+fine-grained data access down to the level of individual files, and allows for
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+tracking future updates. In order to use this repository for data retrieval,
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+[DataLad](https://www.datalad.org/) is required. It is a free and
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+open source command line tool, available for all major operating
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+systems, and builds up on Git and [git-annex](https://git-annex.branchable.com/)
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+to allow sharing, synchronizing, and version controlling collections of
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+large files. You can find information on how to install DataLad at
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+[handbook.datalad.org/en/latest/intro/installation.html](http://handbook.datalad.org/en/latest/intro/installation.html).
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+
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+### Get the dataset
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+
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+A DataLad dataset can be `cloned` by running
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+
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+```
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+datalad clone <url>
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+```
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+
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+Once a dataset is cloned, it is a light-weight directory on your local machine.
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+At this point, it contains only small metadata and information on the
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+identity of the files in the dataset, but not actual *content* of the
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+(sometimes large) data files.
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+
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+### Retrieve dataset content
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+
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+After cloning a dataset, you can retrieve file contents by running
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+
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+```
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+datalad get <path/to/directory/or/file>`
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+```
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+
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+This command will trigger a download of the files, directories, or
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+subdatasets you have specified.
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+
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+DataLad datasets can contain other datasets, so called *subdatasets*.
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+If you clone the top-level dataset, subdatasets do not yet contain
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+metadata and information on the identity of files, but appear to be
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+empty directories. In order to retrieve file availability metadata in
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+subdatasets, run
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+
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+```
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+datalad get -n <path/to/subdataset>
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+```
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+
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+Afterwards, you can browse the retrieved metadata to find out about
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+subdataset contents, and retrieve individual files with `datalad get`.
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+If you use `datalad get <path/to/subdataset>`, all contents of the
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+subdataset will be downloaded at once.
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+
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+### Stay up-to-date
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+
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+DataLad datasets can be updated. The command `datalad update` will
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+*fetch* updates and store them on a different branch (by default
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+`remotes/origin/master`). Running
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+
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+```
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+datalad update --merge
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+```
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+
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+will *pull* available updates and integrate them in one go.
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+
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+### Find out what has been done
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+
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+DataLad datasets contain their history in the ``git log``.
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+By running ``git log`` (or a tool that displays Git history) in the dataset or on
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+specific files, you can find out what has been done to the dataset or to individual files
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+by whom, and when.
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+
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+### More information
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+
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+More information on DataLad and how to use it can be found in the DataLad Handbook at
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+[handbook.datalad.org](http://handbook.datalad.org/en/latest/index.html). The chapter
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+"DataLad datasets" can help you to familiarize yourself with the concept of a dataset.
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