Eigen
3.3.9

Eigen defines several typedef shortcuts for most common 1D and 2D array types.
The general patterns are the following:
ArrayRowsColsType
where Rows
and Cols
can be 2
,3
,4
for fixed size square matrices or X
for dynamic size, and where Type
can be i
for integer, f
for float, d
for double, cf
for complex float, cd
for complex double.
For example, Array33d
is a fixedsize 3x3 array type of doubles, and ArrayXXf
is a dynamicsize matrix of floats.
There are also ArraySizeType
which are selfexplanatory. For example, Array4cf
is a fixedsize 1D array of 4 complex floats.