Delet the values less than Zero from 2d Array

[Khallod]

Hellow,

If I have a twice of 2d -array-like the attached.

as you can see, the first column in the two arrays have the same sequence, but the starting points are different. 

i want to generate a new array contains in the first column the same column of the input arrays. and the second column is the sum of the second column of the two input array. it's easy to add the values but the problem is how to add a similar point. by another way can I delete all the values less than zero from the input arrays, then the two arrays will be started with zero and will possible to add them,

I have tried to do something like the attached but the results not the expected

[Khallod]

actually i solved the problem as the attached .vi.

but if you have something simpler please guide me 

[Yamaeda · Accepted solution]

This seems to work.

[jamiva · Accepted solution]

In the OP case, the array's x values are identical after deleting the start values that are less than zero. Here is another version that's a little more generic. In my particular applications, I cannot guarantee that all x values are identical between the two arrays (i.e, adding antenna gain to a frequency spectrum).