Changing data type of columns

[HanhDo]

Hi everyone,

I would like to change data type of about 60 columns from integer to double at the same time.

I used Column rename which has the option of changing data type but I have to repeat similar procedure (select and change the type) for each of 60 columns.

I was wondering is there any node that allows to do this action for all columns at once?

Thank you very much for your help
Hanh

[iperez]

Hi,

You can use the String Manipulation (Multicolumn) with the following formula toDouble(string($$CURRENTCOLUMN$$))

[mlauber71]

The rename node is not a good option to change types unfortunately

KNIME nodes corrupting on multiple computers

OK I have a theory of what is going on with the rename node and the changed column types. It seems the rename node stores the information of which type it should assign to a column based on the originating type of the column in question. An integer would have other possibilities to be turned into than a Double. [image] [image] The corresponding numbers are now stored in an XML file “settings.xml” If I would now rename the integer into double and the Double into Fuzzy like this [image] T…

[ipazin]

Hello @HanhDo,

I would use Math Formula (Multi Column) node. And why changing column type to double? Check this topic for more:

Integer to Double with Math Formula (Multi Column)

Hi, there are already several posts concerning Integer to Double, but from my point of view it is still not solved. How do I turn multiple integer columns automatically in to double columns? There is a node double to int, but the other direction is still missing (int to double). The Math formula (multi column) does the job [Integer to Double Using Math], but strangely only for manual column selection. Why is the type selection missing? I have many int columns distributed amoung double columns…

Br,
Ivan

[HanhDo]

Hi,
Thanks @iperez
Unfotunately, string manipulation node only works with rows in single column ;/
Br
Hanh

[HanhDo]

Hi @ipazin,
yeah, this is exactly what I actually wanted to look for.
Thanks a lot for your help
Hanh

[iperez]

@HanhDo You are right, that’s why the suggested node is the Multicolumn String Manipulation one:

[HanhDo]

ahhhh, ukie, now I got it. Thank a lots
Hanh