get_data.sh

#!/usr/bin/env bash

# from https://github.com/sorki/python-mnist/blob/master/get_data.sh
# BSD License:
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# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, and the entire permission notice in its entirety,
#    including the disclaimer of warranties.
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#    documentation and/or other materials provided with the distribution.
# 3. The name of the author may not be used to endorse or promote
#    products derived from this software without specific prior
#    written permission.
#
# THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
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# WHICH ARE HEREBY DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE
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# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
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# USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
# DAMAGE.

if [ -d data ]; then
    echo "data directory already present, exiting"
    exit 1
fi

mkdir data
wget --recursive --level=1 --cut-dirs=3 --no-host-directories \
  --directory-prefix=data --accept '*.gz' http://yann.lecun.com/exdb/mnist/
pushd data
gunzip *
popd