How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Forward and central difference stencils with bounded evaluation errors
Definition
Let be open, , and . When , the forward difference of is
When , the central difference is
An evaluation with absolute error bound is a value with at each requested point . The corresponding inexact quotients are obtained by replacing each in the displayed stencil by . The bound is absolute and applies separately to each call; no correlation or relative-error assumption is included.
Depends on
Used by
- Richardson extrapolation for a central difference with a fourth-order remainder Definition
- A quadratic attains the forward truncation bound and exhibits the balanced noisy step Example
- A bounded fifth derivative gives the central-difference expansion required by Richardson extrapolation Lemma
- Forward and central differences have first- and second-order error bounds Theorem
- Richardson extrapolation cancels the second-order term with a fourth-order remainder Theorem
Dependency tree · two levels
2 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- Tobin A. Driscoll and Richard J. Braun, Fundamentals of Numerical Computation, finite differences (standard reference, not scraped)
- Andreas Buttenschoen, Introduction to Scientific Computing, Numerical Differentiation (standard reference, not scraped)