CenteredInterval

CenteredInterval[x,dx] for real numbers x and dx gives a centered interval that contains the real interval {a∈|x-dx≤a≤x+dx}.

CenteredInterval[x+ y,dx+ dy] gives a centered interval that contains the complex rectangle {a+ b∈|x-dx≤a≤x+dx∧y-dy≤b≤y+dy}.

CenteredInterval[c] for an approximate number c gives a centered interval that contains all values within the error bounds of c.

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