Tables will read / write standard CSV (comma-separated values) and TSV (tab..)

To capture the type and shape of the columns, we support the standard header formatting from C++ emergent -- we weren't able to find any more widely supported standard (please let us know if there is one that we've missed -- easy to support!)

Here is the mapping of special header prefix characters to standard types:

'$': etensor.STRING,
'%': etensor.FLOAT32,
'#': etensor.FLOAT64,
'|': etensor.INT64,
'@': etensor.UINT8,
'&': etensor.STRING,
'^': etensor.BOOl,

Columns that have tensor cell shapes (not just scalars) are marked as such with the first such column having a <ndim:dim,dim..> suffix indicating the shape of the cells in this column, e.g., <2:5,4> indicates a 2D cell Y=5,X=4. Each individual column is then indexed as [ndims:x,y..] e.g., the first would be [2:0,0], then [2:0,1] etc.

Here's a TSV file for a scalar String column (Name), a 2D 1x4 tensor float32 column (Input), and a 2D 1x2 float32 Output column.

_H:	$Name	%Input[2:0,0]<2:1,4>	%Input[2:0,1]	%Input[2:0,2]	%Input[2:0,3]	%Output[2:0,0]<2:1,2>	%Output[2:0,1]
_D:	Event_0	1	0	0	0	1	0
_D:	Event_1	0	1	0	0	1	0
_D:	Event_2	0	0	1	0	0	1
_D:	Event_3	0	0	0	1	0	1