locate the number of layers and corresponding thicknesses below a given line

[fahmed-2]

Hello All,

I have a system in which there are "N" number of  black layers and each layer will have random thicknesses.  Then, I want to put a red line on top of any black layer. Whenever I do so, I want to find the number of layers existing only below the red line and also the corresponding layer thicknesses. If the red line ends at the end of the lowest black layer, it should not find any layers below. I can do the worksheet if the red line is present at the top black line but am unable to do so if it stays otherwise. Please help. I have attached my work image for reference. Thank you

[LucMeekes · Accepted solution]

1. You should attach you Prime worksheet.

2. Unclear task. Provide example(s) with input and desired output.

Success!

Luc

[Werner_E]

Your questions sounds like your goal is a drawing, not a calculation.
I don't think that  thats your intention, but your problem sure needs clarification.

It may also help if you speak in terms of math and Prime objects rather than "system of black layers" or "red line".

I guess that you have a vector of arbitrary numbers (the "system of black layers") and an extra number (the "red line").

You have to specify the meaning of this "red number". Is it the number of the "layer" you want to put the red line on top?

If that's what you intend then you just are looking for a function which gives you the sum of all elements in a vector starting from this index

Or is the "red number" the sum of the elements above the "red line", Then you would have to specify what should happen if that number is somewhere in between of a "layer" - should it be split like in this thread?
https://community.ptc.com/t5/Mathcad/Unable-to-extract-a-value-from-a-matrix/m-p/886054/highlight/true#M207462

BTW, it would help if you comment on answers given and say, if the provided suggestion was somewhere near to what you were looking for.

[fahmed-2]

Thank you @LucMeekes and @Werner_E . I have solved the problem