# dataiter.DataFrameColumn

[`__init__()`](#dataiter.DataFrameColumn.__init__)
[`nrow`](#dataiter.DataFrameColumn.nrow)

### *class* dataiter.DataFrameColumn(object, dtype=None, nrow=None)

A column in a data frame.

DataFrameColumn is a subclass of [`Vector`](vector.md#dataiter.Vector). See the vector
documentation for relevant properties and methods.

#### \_\_init_\_(object, dtype=None, nrow=None)

Return a new data frame column.

dtype is the NumPy-compatible data type for the vector. Providing
dtype will make creating the vector faster, otherwise the appropriate
data type will be guessed by introspecting the elements of object,
which is potentially slow, especially for large objects.

If provided, nrow is the row count to produce, i.e. the length to
which object will be broadcast.

```pycon
>>> di.DataFrameColumn([1, 2, 3], int)
[ 1 2 3 ] int64
>>> di.DataFrameColumn([1], int, nrow=10)
[ 1 1 1 1 1 1 1 1 1 1 ] int64
```

#### *property* nrow

Return the amount of rows.