Importing and Exporting (I/O)

Importing data from tabular data files

To read data from a CSV-like file, use the readtable function:

{docs}
readtable

readtable requires that you specify the path of the file that you would like to read as a String. To read data from a non-file source, you may also supply an IO object. It supports many additional keyword arguments: these are documented in the section on advanced I/O operations.

Exporting data to a tabular data file

To write data to a CSV file, use the writetable function:

{docs}
writetable

Supplying DataFrames inline with non-standard string literals

You can also provide CSV-like tabular data in a non-standard string literal to construct a new DataFrame, as in the following:

df = csv"""
    name,  age, squidPerWeek
    Alice,  36,         3.14
    Bob,    24,         0
    Carol,  58,         2.71
    Eve,    49,         7.77
    """

The csv string literal prefix indicates that the data are supplied in standard comma-separated value format. Common alternative formats are also available as string literals. For semicolon-separated values, with comma as a decimal, use csv2:

df = csv2"""
    name;  age; squidPerWeek
    Alice;  36;         3,14
    Bob;    24;         0
    Carol;  58;         2,71
    Eve;    49;         7,77
    """

For whitespace-separated values, use wsv:

df = wsv"""
    name  age squidPerWeek
    Alice  36         3.14
    Bob    24         0
    Carol  58         2.71
    Eve    49         7.77
    """

And for tab-separated values, use tsv:

df = tsv"""
    name    age squidPerWeek
    Alice   36  3.14
    Bob 24  0
    Carol   58  2.71
    Eve 49  7.77
    """