Insert point.ByCoordinates from excel - ERROR

Hello all!
I’d like to ask some help in Dynamo.I am a beginner but I am watching video, trying to build up nodes and my goal is to create surfaces from a list of coordinates. But I run into a problem.

Could you help me to find what the problem is?
Warning text:Warning: Point.ByCoordinates expects argument type(s) (double, double, double), but was called with (string, string, string).

I read about some solutions to the problem, for a exempel that the data from Excel is coming in as strings (text) and I should convert this to a number- use the String.ToNumber node.

But I dont know where I should use String.ToNumber in my code…and i dont know how to connect that node to others.

Can you show me please how I can solve it?

regards, Davide

Hi and welcome, could you please share a screenshot of the Excel file? also can you make sure there are no null values (blank cells, text that was not converted to number, etc.)

Hi Paolo, thank you for your answer!
I have checked my excel file, as you have recommended, and three columns had number as text. I change the proprieties for the columns and the script runs correct now. The problem was into my excel file. I will keep attention in the future about the right format of my values!
Thank you for your tips!
Regards, Davide