replace or change of values in a column

[AxelatKnime]

Hello,
in a dataset all wrong or missing values are filled by a wild fix number. I want to replace this number by an empty cell (or ? as missing value).
Do you have an idea to do it?
Thank you
Axel

[elsamuel]

One approach is to use the Column Expressions node:

if (column("your_column") == your_value)
{
    missingValue()
}
else
{
    column("your_column")
}

[ipazin]

Hello @AxelatKnime,

how are you reading this data into KNIME? Some reader nodes have option to define Missing Value Pattern so you can automatically replace your wild number with missing value.

Additionally you can use following two approaches from above workflow examples:

Looping over Every Column – ipazin

Replace Values over Multiple Columns – ipazin

And finally if your columns are by any chance all string types you can use String Manipulation (Multi Column) as a one node solution

Br,
Ivan

[AxelatKnime]

Thank you all. It works.
Axel