`fxsubmapping=``fxmap``k`procedure`fxsubmapping<``fxmap``k`procedure`fxsubmapping<=``fxmap``k`procedure`fxsubmapping>``fxmap``k`procedure`fxsubmapping>=``fxmap``k`procedureProcedures that return a fxmapping containing the associations of

*fxmap*whose keys are equal to, less than/less than or equal to/greater than/greater than or equal to*k*. Note that the result of`fxsubmapping=`contains at most one element.Examples:

(fxmapping->alist (fxsubmapping= (fxmapping 0 'a 1 'b 2 'c 3 'd) 2)) ⇒ ((2 . c)) (fxmapping->alist (fxsubmapping< (fxmapping 0 'a 1 'b 2 'c 3 'd) 2)) ⇒ ((0 . a) (1 . b)) (fxmapping->alist (fxsubmapping>= (fxmapping 0 'a 1 'b 2 'c 3 'd) 2)) ⇒ ((2 . c) (3 . d))