# datatable.FExpr.__lshift__()¶

Shift x by y bits to the left, i.e. x << y. Mathematically this is equivalent to $$x\cdot 2^y$$.

If x or y are multi-column expressions, then they must have the same number of columns, and the << operator will be applied to each corresponding pair of columns. If either x or y are single-column while the other is multi-column, then the single-column expression will be repeated to the same number of columns as its opponent.

The left-shift operator can only be applied to integer columns, and the resulting column will have the same stype as its argument.

## Parameters¶

x
,
y
FExpr

The arguments must be either FExprs, or expressions that can be converted into FExprs.

return
FExpr

An expression that evaluates x << y.