interp_scattered — MATH interp_poly op

• 데이터 종류: points × signal × points → table

• 호출: import fullseye as fs; fs.ledger.interp_scattered(points, values, query, method='linear', fill_value=nan, rescale=False, neighbors=None)(구현을 직접 호출하려면 import mathops; mathops.interp_scattered(points, values, query, method='linear', fill_value=nan, rescale=False, neighbors=None), 원장에서 가져오려면 opsmath.get("interp_scattered"))

사용법

> 이 연산자의 설명은 아직 번역이 없습니다. 원문을 그대로 싣습니다.

Values at *query* from scattered samples — sensor nets, boreholes, weather.

interp_linear and interp_cubic need samples on a sorted 1-D axis. A great deal of measurement does not arrive that way: temperature sensors bolted wherever a rack allowed, boreholes drilled where access permitted, weather stations placed by history. This is the N-D scattered entry point (scipy.interpolate), and it returns how much of the answer was not interpolation at all.

*method*:

"nearest"

the value of the closest sample. Defined everywhere, and never

overshoots, but it is a staircase: on a smooth field the step itself

becomes a false feature. Measured on a smooth 3-D field sampled at 0.60,

the nearest-neighbour reconstruction leaves a residual of 0.975 units

where the sensor noise is only 0.15 — 6.5 times the noise, and none of

it is noise.

"linear"

barycentric interpolation on a Delaunay triangulation. Never exceeds the

surrounding samples, and is undefined outside their convex hull.

"rbf"

a thin-plate radial basis function through every sample. Smooth and

defined everywhere, but it overshoots its own nodes: measured on the

same field it returns peaks 1.372 times the sampled height, which is a

37 % over-statement of a hot spot that no interpolation of the data can

justify.

The point of the outside return value. Sensors sit inside a room, a site, a country; the corners are always outside their hull. Ask a linear interpolator there and it returns fill_value, or, if a caller quietly falls back to nearest, it returns a different method's answer under the first method's name. Measured on a 12 x 8.4 x 3.0 m room sampled at 1.20 m spacing, 71.2 % of the evaluation grid lay outside the hull. A number that large has to be visible, so it is returned rather than logged.

Parameters

points : (n, d) array_like

Sample coordinates. 1-D input is accepted and treated as (n, 1).

values : (n,) array_like

query : (m, d) or (..., d) array_like

Where to evaluate. The leading shape is preserved in the result.

method : {"linear", "nearest", "rbf"}

fill_value : float

Returned outside the convex hull for "linear". "nearest" and

"rbf" are defined everywhere and ignore it.

rescale : bool

Normalise each axis before triangulating. Needed when the axes have very

different units (metres against millimetres); ignored by "rbf".

neighbors : int or None

"rbf" only: solve against the *k* nearest samples instead of all of

them. The global solve is O(n^3); measured on 5000 query points in 3-D,

it costs 0.55 / 1.76 / 7.53 s at 1400 / 4000 / 8000 samples, while

neighbors=48 costs 0.38 / 0.55 / 0.81 s. Below a few thousand

samples the global solve is fine and exact — the knob earns its place

above that. None keeps the exact global solution.

Returns

dict

value (query shape), outside (bool mask, query shape, of query

points beyond the convex hull of the samples), outside_fraction,

method, n_points.

Fail-closed: fewer samples than d + 1 cannot define a simplex, and raises ValueError rather than returning a field made of fill_value.

See also

interp_linear : the sorted 1-D case, which is cheaper and needs no hull.

패밀리 공통 입력 계약(fail-closed)

mathops 의 모든 연산자는 입력을 검증한 뒤에 계산합니다(조용히 통과시키지 않습니다):

• complex 입력은 ValueError —— float64 로의 강제 변환은 허수부를 조용히 버립니다(numpy 는 ComplexWarning 만 내고 「그럴듯하게 틀린」 실수를 돌려줍니다). .real/.imag/abs() 를 명시하거나 복소수를 다루는 complexops 를 쓰세요.

• masked 요소가 있는 masked array 는 ValueError —— 마스크를 벗겨 아래 원값을 쓰는 암묵 변환을 거부합니다. 채울지 버릴지를 명시하세요.

• NaN/Inf 는 모든 입력에서 ValueError(개수를 명시하고 거부 —— 결과 전체로 전파되므로).

• 형상은 엄격: 1-D 와 2-D 를 암묵적으로 승격·브로드캐스트하지 않습니다(vector 슬롯에 matrix, matrix 슬롯에 vector 는 ValueError. reshape 를 명시하세요).

• 크기 상한: 행렬을 받는 연산자와 stat_histogram 의 bins 는 mathops.MAX_ELEMENTS(2^26 ≈ 6700 만 요소)를 넘으면 ValueError.

자세한 사용 가이드

• math_metrology 패밀리 가이드

참고(샘플 데이터·문헌)

• 샘플 데이터 카탈로그(DL URL / 라이선스) —— 2-D 는 skimage.data(BSD/public)+ 합성, 3-D 는 실데이터 소스(Stanford/PDS 등)의 DL URL.

• 연산자의 내력·참고문헌 —— 이 연산자 족의 바탕이 된 연구/기법의 출처.

• 알고리즘의 정전(저자·연도)과 용도는 위의 패밀리 사용 가이드에 적혀 있습니다.

실행 가능한 예제(이 연산자를 실제로 호출하는 검증된 샘플)

• poc_datacenter_thermal_field — py -3.11 examples/poc_datacenter_thermal_field.py

• poc_multibeam_bathymetry — py -3.11 examples/poc_multibeam_bathymetry.py

• poc_stockpile_volume — py -3.11 examples/poc_stockpile_volume.py

타입이 이어지는 다음 연산자(table 를 입력으로 받는 것)

dynsys_poincare_section · dwt_inverse · chebyshev_eval_nd

같은 카테고리(interp_poly)

interp_linear · interp_cubic · poly_fit · poly_eval · poly_roots


*Provenance: mathops.py — MATH 연산자 레지스트리. 이 op 노트는 tools/opdocs.py md 가 자동 생성합니다(직접 편집하지 마세요).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.