If you have Kutools, it is very simple. And actually you may be able to do this with an excel function also.
But with Kutools, it is like this:

Copy your column of figures into an extra column, so that you have 2 columns with exactly the same figures there.

Now all you have to do is remove all the negative numbers from the first column, and all the positive numbers from the second column, and your result is 2 columns, one with negs, one with positives.

So, with the first column, select the column contents fully and then open Kutools, and pick Select tab in the drop down, then pick Select Specific Cells.
Now in Selection Type, click the radio button next to Cell, then GREATER THAN or Equal to 0 (zero). So you are selecting all the cells that have a number in them which is greater than or equal to 0, meaning positive numbers.

Kutools will select all of the positive numbers, so when this is done, simply click Delete, and it will delete all the positive numbers from this list.

Then repeat the process in the other column, only this time you will choose, "LESS THAN or Equal to 0 (zero). And the result will be that all the negative numbers are selected, ready for you to delete. Delete them.

Now you are left with 2 columns, one is positive, one is negative, and you have retained your row positions for each one.

The above process may be possible using a filter in excel, without the need for Kutools, but I am not sure how.

Cheers!