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How to sum elements of nested list in Autolisp?

I am beginning to code in LISP, so I don't know much. I have a list of coordinates, and I want to add each x and y for each point and put them into a new variable. the list: ((587243.0 4.04705e+006) (587242.0 4.04704e+006) (587228.0 4.04704e+006) (587226.0 4.04704e+006) (587227.0 4.04705e+006) (587243.0 4.04705e+006))

Thanks in advance.

Solution

  • You can use a combination of mapcar & apply for this task, e.g.:

    (setq lst
   '(
        (587243.0 4.04705e+006)
        (587242.0 4.04704e+006)
        (587228.0 4.04704e+006)
        (587226.0 4.04704e+006)
        (587227.0 4.04705e+006)
        (587243.0 4.04705e+006)
    )
)
(mapcar '(lambda ( x ) (apply '+ x)) lst)

    (4.63429e+06 4.63428e+06 4.63427e+06 4.63427e+06 4.63428e+06 4.63429e+06)