File name including iteration

[JWebb]

Hello all. Normally, I can figure out issues I am having by reading around online, but I am stumped so I think I need to ask the experts. I have a loop set up where I cut a spreadsheet into manageable chunks (because our system gives up over a certain number of rows) and writes them into .csv files. That saves us a lot of manual cutting and pasting.

What I would like to is to be able to have file names of “String”+$${iCurrentIteration}$$, so I can get a list of .csv files which appear as below:

MyFile_Part0.csv
MyFile_Part1.csv
MyFile_Part2.csv

Currently, I have the create file name node set up to have base file name using the CurrentIteration variable, but I can’t figure out how to get the string in front of it.

[ipazin]

Hello @JWebb,

welcome to KNIME Community!

You can use join() function from String Manipulation (Variable) to create flow variable with desired file name.

join(MyFile,"_Part",$${iCurrentIteration}$$)

You don’t need Create File Name if I got you right. Also if “MyFile” is name of file you are reading you can automate this by creating a flow variable In Excel Reader holding file name. See here for more: https://docs.knime.com/latest/analytics_platform_flow_control_guide/index.html#creating-local-flow-variables

Br,
Ivan

[JWebb]

Hello Ivan, thanks for the suggestion. That looks far more promising! I’m a bit stuck on applying that formula though. I have not come across the error before as it’s the first time I am using this node, so apologies if this is a really novice mistake! I even tried cutting it down to a really simple string so I thought just have “Part0.csv” etc., but to no avail.

[elsamuel]

It would be helpful if you shared the workflow, or at least showed the configuration of the node.

The error message references line 64. What do you have on line 64?

[JWebb]

Fresh day, fresh brain and I figured it out. It’s because the current iteration is an integer, not a string. That was all All fixed and it works with a test file! Thanks for your help everyone.

[ipazin]

Hello @JWebb,

glad you figured it out on your own

You can mark specific reply as solution (button is hidden behind 3 dots in right bottom corner of every reply). Helps us keep forum clean.

Also make sure to explore KNIME Hub and possibly contribute with your solutions

Br,
Ivan

[JWebb]

Thanks Ivan. I have had a look and will assist where I can, but I’ve not been using Knime for that long!