Math Formula Node - Unable to parse m_expression Syntax error

[JonahGlsr]

Hey,

i’ve got a problem with the math formula node in Knime.

I’m using a javascript view node to create an calculator widget. In this widget i can create formulas like this as a flowvariable on output:

$column1$ - $column2$

I now want to use an math forumula node to use this formula to do the calculations based on widget input.

When i try to use the flow variable as an input to the node (“expression” field in the flow variable input of the math node) i get the following error: “Unable to parse m_expression Syntax error”

Do you have an idea what I’m doing wrong?
Does the expression field require an specific format? If yes, how do i change the format?

Best regards,
Jonah

[ActionAndi]

Hi,
is there a chance that you can share a simplified example workflow?
Andreas

[JonahGlsr]

Hi Andreas,

i’ve attached a simplified version of my workflow.
Math Formula Node problem.knwf (83.0 KB)

If you need more information, let me know.

(my company uses KNIME 5.2.6)

Thanks

[haozi04]

Remove the   from the buttons in the html code. They are not considered as normal blanks and caused this error.

(I have to say this is really subtle )

[JonahGlsr]

Oh I see.
I’d never thought this would be the problem.

Thanks for your help