cplx_domain_colour — MATH complex op

• 資料種類:cimage → rgbimage

• 呼叫: import fullseye as fs; fs.ledger.cplx_domain_colour(field, gamma=1.0, bands=0.0, saturation=1.0)(要直接呼叫實作,import mathops; mathops.cplx_domain_colour(field, gamma=1.0, bands=0.0, saturation=1.0);從台帳取用則 opsmath.get("cplx_domain_colour"))

用法

定義域著色 —— 把複場變成可以讀懂的 RGB 影像。

> 以下的詳細說明為原文 —— 摘要與標題已翻譯。

Hue carries `arg(z)` (one full turn of the colour wheel per turn of the

argument, red at `arg = 0); value carries |z|` through the **strictly

increasing** map `t/(1+t) with t = |z|**gamma`, so a zero is exactly

black, `|z| = 1` is half brightness and a large modulus saturates at full

brightness. The saturation is not dropped far from the origin, so the

hue — and with it the argument — stays readable everywhere; pass

`saturation = 0` for a plain grey ramp of the modulus alone. With

`bands = 0` (the default) the

brightness is monotone in `|z|`, which means the picture is *invertible*:

the argument comes back out of the hue and the modulus out of the value.

★The picture proves a theorem. Walk a small circle around a zero of

order *m* and the hue cycles through the colour wheel exactly *m* times;

around a pole of order *m*, *m* times the other way. That is the argument

principle, read off the image with no numbers — and this family's

`cplx_winding_number` counts the same integer from the field itself, so

the drawing and the arithmetic check each other.

Parameters

----------

field : complex 2-D array (`cimage`)

Typically from :func:cplx_rational_field.

gamma : float > 0

Compresses (`<1) or stretches (>1`) the modulus ramp.

bands : float >= 0

Classic modulus contours: `bands` shading cycles per decade of

`|z|`. Non-zero breaks monotonicity (that is the point — it draws

level lines), so the inverse-mapping guarantee above holds only at 0.

saturation : float in [0, 1]

Raises `ValueError`: not a 2-D complex array; non-finite samples

(a pole sampled exactly — see :func:cplx_rational_field); `gamma <= 0`;

`bands < 0; saturation` outside [0, 1].

HALCON: no operator.

該族通用的輸入契約(fail-closed)

mathops 的每個運算子都先檢驗輸入再計算(不讓任何東西無聲通過):

• **complex 輸入一律 ValueError** —— 強制轉成 float64 會無聲丟掉虛部(numpy 只發一個 ComplexWarning,然後回傳一個「看似合理卻是錯的」實數)。請明確寫出 .real/.imag/abs(),或改用支援複數的 complexops。

• **含被遮罩元素的 masked array 一律 ValueError** —— 拒絕「剝掉遮罩直接使用下面原值」的隱式轉換。請明確選擇填補還是丟棄。

• **所有輸入中的 NaN/Inf 一律 ValueError**(明確給出個數後拒絕 —— 它會汙染整個結果)。

• 形狀嚴格:不對 1-D 與 2-D 做隱式提升或廣播(向量槽位收到矩陣、矩陣槽位收到向量都是 ValueError;請明確 reshape)。

• 尺寸上限:接受矩陣的運算子與 stat_histogram 的 bins,超過 mathops.MAX_ELEMENTS(2^26 ≈ 6700 萬個元素)即 ValueError。

詳細使用指南

• math_metrology 族使用指南

參考(範例資料・文獻)

• 範例資料目錄(下載 URL / 授權) —— 2-D 用 skimage.data(BSD/公有領域)加合成圖,3-D 給出真實資料源(Stanford/PDS 等)的下載 URL。

• 運算子來歷與參考文獻 —— 該運算子族所依據的研究/方法出處。

• 演算法的正典(作者・年份)與用途見上面的族使用指南。

可執行的範例(實際呼叫該運算子並已驗證的樣例)

• poc_complex_plane_fields — py -3.11 examples/poc_complex_plane_fields.py

型別可銜接的下一個運算子(可接受 rgbimage 作為輸入)

—

同類別(complex)

cplx_contour_circle · cplx_poly_eval · cplx_contour_integral · cplx_winding_number · cplx_cauchy_value · cplx_argument_principle · cplx_laurent_coeffs · cplx_joukowski


*Provenance: mathops.py — MATH 運算子登記表。本條目由 tools/opdocs.py md 自動產生(請勿手動編輯)。*

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