# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/\s*\[\s*\[\s*\[\s*([+-]?\d+(\.\d*)?([EeDd][+-]?\d+)?)\s*,\s*([+-]?\d+(\.\d*)?([EeDd][+-]?\d+)?)\s*\]\s*,\s*\[\s*([+-]?\d+(\.\d*)?([EeDd][+-]?\d+)?)\s*,\s*([+-]?\d+(\.\d*)?([EeDd][+-]?\d+)?)\s*\]\s*,\s*\[\s*([+-]?\d+(\.\d*)?([EeDd][+-]?\d+)?)\s*,\s*([+-]?\d+(\.\d*)?([EeDd][+-]?\d+)?)\s*\]\s*\]\s*\]\s*/{"\1,\4","\7,\10","\13,\16"}\n/gm;t' <<< "[[[5,3],[2,8],[6,-3]]]
[ [ [ 5.23 , 3.42 ] , [ 2. , 8.17 ] , [ 6 , -3 ] ] ]
[[
[ 5, 3],
[ 2, 8.43],
[ -6.18,-3]
]]
[
[
[
5,
3.141592653
],
[
2.718281828,
8
],
[ 0.618,
-35.16e-17
]
]
]
"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html