AI與程式實戰應用

AI·深度學習與3D遊戲引擎數學實戰指南

透過一行總結與程式碼片段,直觀了解數學公式如何驅動大語言模型、3D圖形渲染、量化金融與密碼學。

The Mathematical Pipeline Behind ChatGPT & Claude Token Generation
Attention⁡(Q,K,V)=softmax⁡ ⁣(QKTdk)V\operatorname{Attention}(Q,K,V) = \operatorname{softmax}\!\left(\frac{QK^T}{\sqrt{d_k}}\right)V
  • Dot Product (#L02): Measures Query-Key semantic alignment across tokens
  • Matrix Multiplication (#L04): Parallelizes multi-head projection on GPU Tensor Cores
  • Softmax (#P10): Converts raw logits into temperature-controlled token probabilities
  • Cross-Entropy (#P09) & Chain Rule (#C03): Evaluates loss and backpropagates gradients

Large Language Models (LLM & Transformer)

Computes contextual token similarity via scaled dot products, normalizes weights with Softmax, and backpropagates Cross-Entropy Loss via the Chain Rule.

#L02 · 線性代數

向量點積(內積)與餘弦相似度

a⋅b=∑i=1naibi=∥a∥∥b∥cos⁡θ\mathbf{a} \cdot \mathbf{b} = \sum_{i=1}^{n} a_i b_i = \|\mathbf{a}\|\|\mathbf{b}\|\cos\theta

ChatGPT自注意力機制(Q·K^T點積)、RAG向量資料庫餘弦檢索與3D圖形蘭伯特漫反射光照(N·L)

const cosSim = (a:number[], b:number[]) => dot(a,b) / (norm(a) * norm(b));
#L04 · 線性代數

矩陣乘法與線性變換複合 (GEMM)

(AB)ij=∑k=1nAikBkj(AB)_{ij} = \sum_{k=1}^{n} A_{ik} B_{kj}

佔據NVIDIA GPU張量核心90%算力的AI深度學習(Y=XW)與3D圖形引擎MVP座標變換流水線

const matMul2 = (A:number[][], B:number[][]) => [[A[0][0]*B[0][0]+A[0][1]*B[1][0], A[0][0]*B[0][1]+A[0][1]*B[1][1]]];
#P02 · 概率·統計

條件概率與乘法定理

P(A∣B)=P(A∩B)P(B),P(A∩B)=P(B)P(A∣B)P(A \mid B) = \frac{P(A \cap B)}{P(B)}, \quad P(A \cap B) = P(B)P(A \mid B)

GPT等大語言模型(LLM)根據前文詞序列計算下一個詞的條件概率 P(w_t | w_<t) 的核心生成公式。

const pAgivenB = (pAB, pB) => pB > 0 ? pAB / pB : 0;
#P09 · 概率·統計

香農資訊熵與交叉熵損失 (Cross-Entropy)

H(P,Q)=−∑xP(x)log⁡Q(x)=H(P)+DKL(P∥Q)H(P, Q) = -\sum_x P(x) \log Q(x) = H(P) + D_{\mathrm{KL}}(P \parallel Q)

大語言模型(LLM)訓練、圖像分類器等幾乎所有現代分類與生成式AI的標準損失函數(Cross-Entropy Loss)。

const bceLoss = (y, yHat) => -(y * Math.log(yHat + 1e-9) + (1 - y) * Math.log(1 - yHat + 1e-9));
#P10 · 概率·統計

Softmax函數與隨機梯度下降 (SGD)

σ(z)i=ezi/T∑j=1Kezj/T,θt+1=θt−η∇θL(θt)\sigma(\mathbf{z})_i = \frac{e^{z_i / T}}{\sum_{j=1}^K e^{z_j / T}}, \quad \theta_{t+1} = \theta_t - \eta \nabla_\theta \mathcal{L}(\theta_t)

Transformer自注意力機制、LLM溫度採樣以及所有深度學習優化器(SGD, AdamW)的心臟公式。

const softmax = (zs, T=1) => { const exps = zs.map(z => Math.exp(z/T)); const s = exps.reduce((a,b)=>a+b,0); return exps.map(e => e/s); };
#C03 · 微積分

乘積法則與複合函數鏈式法則 (Chain Rule)

dydx=dydu⋅dudx,(uv)′=u′v+uv′\frac{dy}{dx} = \frac{dy}{du} \cdot \frac{du}{dx},\quad (uv)' = u'v + uv'

深度學習神經網路誤差反向傳播(Backpropagation)與PyTorch自動微分(Autograd)計算圖核心

const dL_dw = dL_dy * dy_du * du_dw; // Backpropagation Chain Rule

全部50個數學公式程式碼實現與AI應用矩陣

#Linear Layer y=wx+b#UI Lerp Animation#Constraint Solver

機器學習單層感知機(y = wx + b)權重偏置建模與UI動畫線性插值(Lerp)

const solveLinear = (a: number, b: number) => -b / a;
#Polynomial Kernel SVM#Symbolic Algebra#Completing Square

機器學習多項式核函數(SVM)特徵映射與計算機代數系統(CAS)符號化簡

const sqSum = (a: number, b: number) => a*a + 2*a*b + b*b;
#IEEE 754 Float#Shader Gamma Correction#Exponential Scaling

IEEE 754浮點數指數編碼與3D圖形渲染伽瑪校正(c^(1/2.2))

const gammaCorrect = (c: number, g = 2.2) => Math.pow(c, 1 / g);
#3D Ray Tracing#Physics Collision#Optimization Parabola

3D光線追蹤(Ray-Sphere)射線與球體相交檢測及物理引擎拋物線彈道碰撞計算

const D = b*b - 4*a*c; const x1 = (-b + Math.sqrt(D)) / (2*a);
#Matrix Trace & Det#Control Theory Poles#Symmetric Polynomials

控制工程系統極點穩定性判別與矩陣特徵值跡/行列式快速校驗

const sumRoots = -b / a; const prodRoots = c / a;
#O(log N) Complexity#Log-Likelihood AI#Information Theory

二分搜尋O(log₂ N)時間複雜度分析與深度學習對數似然(Log-Likelihood)防下溢計算

const logBase = (a: number, x: number) => Math.log(x) / Math.log(a);
#RL Discounted Return#Quant Finance DCF#Algorithm Loop Analysis

強化學習(RL)折扣累積獎勵(∑ γ^t)收斂上界計算與金融複利現值定價

const geoSum = (a: number, r: number, n: number) => a * (1 - Math.pow(r, n)) / (1 - r);
#Bernstein Basis#Dynamic Programming#Combinatorial AI

3D貝茲曲線的伯恩斯坦基多項式構建與集成學習(Ensemble)多數投票機率分析

const nCr = (n: number, k: number): number => k === 0 ? 1 : (n * nCr(n - 1, k - 1)) / k;
#Quantum Computing#RF Signal DSP#2D Rotation

音訊與無線通信FFT複數頻譜分析、量子計算量子位元振幅與碎形圖形渲染

const mag = Math.hypot(re, im); const phase = Math.atan2(im, re);
#RSA Cryptography#Blockchain Security#Hash Table Modulo

HTTPS/金融安全RSA公鑰加密演算法、區塊鏈數位簽章與雜湊表(Hash Table)尋址

const modPow = (a: bigint, e: bigint, m: bigint): bigint => /* binary exp */
#Game Physics Distance#L2 Metric Foundation#CAD Geometry

遊戲引擎碰撞距離計算(Math.hypot)與AI高維特徵空間L2歐氏距離度量的原型

const hypotenuse = (a: number, b: number) => Math.hypot(a, b);
#K-Means & KNN ML#A* Pathfinding#3D Spatial Query

機器學習KNN分類、K-Means聚類距離度量與3D遊戲A*尋路演算法啟發式函數

const dist3D = (dx: number, dy: number, dz: number) => Math.hypot(dx, dy, dz);
#Three.js Radians#Robotics Odometry#Shader Angles

Three.js/WebGL圖形庫標準弧度介面與機器人輪式里程計(l=rθ)位移解算

const degToRad = (deg: number) => (deg * Math.PI) / 180;
#LLM RoPE Encoding#Wave Shader#Circular Orbit

大語言模型Transformer旋轉位置編碼(RoPE)與3D遊戲圓周運動/波浪著色器

const posOnCircle = (r: number, rad: number) => ({ x: r * Math.cos(rad), y: r * Math.sin(rad) });
#Inverse Kinematics IK#GPS Triangulation#Vector Dot Product

機器人機械臂與3D角色骨骼逆運動學(IK)關節角求解及GPS三角測量

const cosC = (a*a + b*b - c*c) / (2 * a * b);
#Rotation Matrix Proof#5G QAM Modulation#Audio DSP

推導2D/3D旋轉矩陣複合運算 R(α)R(β)=R(α+β) 與5G無線通信正交調幅(QAM)解調

const sinAdd = (a: number, b: number) => Math.sin(a)*Math.cos(b) + Math.cos(a)*Math.sin(b);
#Kepler Orbit Sim#Mahalanobis Ellipse#Antenna Optics

人造衛星克卜勒橢圓軌道模擬與機器學習多維高斯協方差橢圓(馬氏距離等高線)

const eccentricity = (a: number, b: number) => Math.sqrt(1 - (b*b)/(a*a));
#3D Globe Mapping#OrbitControls Camera#Spherical Harmonics

3D地球儀360°全景紋理映射、Three.js相機環繞控制(OrbitControls)與量子力學球諧函數

const toXYZ = (r:number, th:number, ph:number) => [r*Math.sin(ph)*Math.cos(th), r*Math.cos(ph), r*Math.sin(ph)*Math.sin(th)];
#3D Mesh Topology#Graph Theory#CAD Manifold Check

3D建模與遊戲引擎多邊形流形網格(Manifold Mesh)拓撲校驗及晶片平面圖佈線

const eulerChar = (V: number, E: number, F: number) => V - E + F;
#SVG & Font Rendering#CSS cubic-bezier#3D Camera Splines

SVG向量圖形、CSS動畫cubic-bezier緩動函數、字型渲染與自動駕駛平滑軌跡規劃

const quadBezier = (p0:number, p1:number, p2:number, t:number) => (1-t)*(1-t)*p0 + 2*(1-t)*t*p1 + t*t*p2;
#Sigmoid & Softmax#Continuous Compounding#Calculus Foundation

深度學習激活函數(Sigmoid/Softmax/GELU)指數核與量化金融連續複利(e^rt)定價

const approxE = (n: number) => Math.pow(1 + 1 / n, n);
#Numerical Differentiation#Physics Velocity#Optimization Extremum

遊戲物理引擎速度/加速度數值微分與深度學習損失函數切線斜率計算

const diff = (f: (x:number)=>number, x: number, h = 1e-5) => (f(x + h) - f(x - h)) / (2 * h);
#Deep Learning Backprop#PyTorch Autograd#Neural Net Training

深度學習神經網路誤差反向傳播(Backpropagation)與PyTorch自動微分(Autograd)計算圖核心

const dL_dw = dL_dy * dy_du * du_dw; // Backpropagation Chain Rule
#Physics RK4 Integrator#3D Rendering Equation#Probability CDF

物理引擎速度到位置數值積分(RK4)、3D渲染方程光照積分與機率累積分佈函數(CDF)

const simpson = (f:(x:number)=>number, a:number, b:number) => ((b-a)/6)*(f(a)+4*f((a+b)/2)+f(b));
#FEM Physics Sim#Fourier Transform Proof#Signal Laplace

工程物理模擬有限元分析(FEM弱形式推導)與傅立葉/拉普拉斯變換微分性質證明

const intXeX = (x: number) => (x - 1) * Math.exp(x) + 1; // ∫_0^x t*e^t dt
#XGBoost 2nd-Order Loss#CPU/GPU Fast Math#Physics Linearization

CPU/GPU超越函數底層快速近似與XGBoost梯度提升樹二階泰勒展開優化

const sinTaylor = (x: number) => x - (x**3)/6 + (x**5)/120 - (x**7)/5040;
#LLM RoPE e^(imθ)#Fourier Basis#Quantum Phase

大語言模型旋轉位置編碼(RoPE: e^(imθ))、FFT複指數基函數與量子計算相位閘

const eulerCis = (theta: number) => ({ re: Math.cos(theta), im: Math.sin(theta) });
#Gradient Descent -∇L#Computer Vision Sobel#Physics Field ∇

百億參數大模型梯度下降(-∇L)訓練與電腦視覺影像邊緣檢測(Sobel算子)

const grad2D = (a:number, b:number, x:number, y:number) => ({ gx: 2*a*x, gy: 2*b*y });
#Audio AI Spectrogram#5G/Wi-Fi OFDM#JPEG/MP3 Compression

AI語音辨識(Whisper梅爾頻譜圖)、MP3/JPEG有損壓縮、5G/Wi-Fi正交頻分複用與MRI醫學成像

const dftBin = (sig: number[], k: number) => sig.reduce((s, x, n) => s + x * Math.cos(2*Math.PI*k*n/sig.length), 0);
#Diffusion AI ODE#Spring Physics UI#Control Engineering

生成式AI擴散模型(Diffusion ODE求解器)、React-Spring彈簧UI動畫與機器人阻抗控制

const zeta = c / (2 * Math.sqrt(m * k)); const w0 = Math.sqrt(k / m);
#L1/L2 Regularization#3D Vector Normalize#Embedding Norm

深度學習L1/L2權重衰減正則化、LayerNorm層歸一化與3D遊戲角色斜向移動速度歸一化

const norm2 = Math.hypot(vx, vy, vz); const unit = [vx/norm2, vy/norm2, vz/norm2];
#LLM Self-Attention Q·K#RAG Vector DB#3D Lighting Shader

ChatGPT自注意力機制(Q·K^T點積)、RAG向量資料庫餘弦檢索與3D圖形蘭伯特漫反射光照(N·L)

const cosSim = (a:number[], b:number[]) => dot(a,b) / (norm(a) * norm(b));
#3D Surface Normal#Physics Torque r×F#Back-face Culling

3D網格三角形表面法線計算、背面剔除(Back-face Culling)與物理引擎剛體扭矩(τ=r×F)

const cross = (a:number[], b:number[]) => [a[1]*b[2]-a[2]*b[1], a[2]*b[0]-a[0]*b[2], a[0]*b[1]-a[1]*b[0]];
#GPU Tensor Cores GEMM#Deep Learning Y=XW#3D MVP Pipeline

佔據NVIDIA GPU張量核心90%算力的AI深度學習(Y=XW)與3D圖形引擎MVP座標變換流水線

const matMul2 = (A:number[][], B:number[][]) => [[A[0][0]*B[0][0]+A[0][1]*B[1][0], A[0][0]*B[0][1]+A[0][1]*B[1][1]]];
#3D Mouse Raycasting#Jacobian Determinant#Normalizing Flows

3D遊戲滑鼠點擊射線拾取逆投影(MVP⁻¹)與生成式AI流模型(Normalizing Flows)雅可比行列式

const det2 = (a:number, b:number, c:number, d:number) => a * d - b * c;
#Linear Solver Ax=b#SPICE Circuit Sim#Normal Equations

SPICE電路模擬器、結構力學有限元求解器與最小二乘正規方程(A^T A x = A^T b)求解

const det = a1*b2 - b1*a2; const x = (c1*b2 - b1*c2)/det; const y = (a1*c2 - c1*a2)/det;
#3D Engine Rotation#LiDAR Point Cloud#Orthogonal Matrix SO(3)

Three.js/Unreal/Unity 3D物體與相機旋轉變換及自動駕駛光達點雲配準(ICP)

const rot2D = (x:number, y:number, r:number) => ({ x: x*Math.cos(r) - y*Math.sin(r), y: x*Math.sin(r) + y*Math.cos(r) });
#Google PageRank#Quantum Mechanics Hψ=Eψ#Spectral Graph Theory

Google搜尋PageRank網頁排名演算法、量子力學薛丁格定態方程(Hψ=Eψ)與橋樑共振模態分析

const tr = a + d; const det = a*d - b*c; const l1 = (tr + Math.sqrt(tr*tr - 4*det))/2;
#LLM LoRA Fine-Tuning#PCA Dimensionality#Recommender System

大語言模型低秩微調(LoRA)、PCA高維特徵降維、推薦系統矩陣分解與影像壓縮

const explainedRatio = (s1:number, s2:number, s3:number) => (s1*s1) / (s1*s1 + s2*s2 + s3*s3);
#Three.js Quaternion#Gimbal Lock Free#Aerospace Attitude

Three.js/Unity/Unreal骨骼動畫平滑插值(SLERP)與無人機/太空船防萬向節死鎖姿態控制

const quatFromAxisZ = (rad: number) => ({ w: Math.cos(rad/2), x: 0, y: 0, z: Math.sin(rad/2) });
#Combinatorics#Search Space#Algorithm Complexity#Feature Selection

用於演算法搜索空間複雜度分析、超參數網格搜索組合數計算以及特徵子集選擇。

const nCr = (n, r) => Array.from({length: r}, (_, i) => (n - i) / (i + 1)).reduce((a, b) => a * b, 1);
#LLM Next-Token#Autoregressive AI#Markov Chains#Probabilistic Graphical Models

GPT等大語言模型(LLM)根據前文詞序列計算下一個詞的條件概率 P(w_t | w_<t) 的核心生成公式。

const pAgivenB = (pAB, pB) => pB > 0 ? pAB / pB : 0;
#Spam Filter#Bayesian Inference#Medical AI Diagnosis#Kalman Filter

直接驅動垃圾郵件過濾(樸素貝氏)、醫療AI診斷校準、自動駕駛卡爾曼/粒子濾波及貝氏超參數優化。

const bayes = (prior, sens, fpr) => (sens * prior) / (sens * prior + fpr * (1 - prior));
#Reinforcement Learning#Batch Normalization#Quant Risk#Weight Initialization

強化學習(RL)期望累計獎勵最大化、深度學習批歸一化(BatchNorm/LayerNorm)及權重初始化的核心公式。

const mean = xs.reduce((a,b)=>a+b,0)/xs.length; const variance = xs.reduce((s,x)=>s+(x-mean)**2,0)/xs.length;
#A/B Testing#Dropout Regularization#CTR Modeling#Game Gacha Math

用於廣告點擊率(CTR) A/B測試、神經網路Dropout掩碼概率建模以及遊戲抽卡概率模擬。

const binomPMF = (n, k, p) => nCr(n, k) * Math.pow(p, k) * Math.pow(1 - p, n - k);
#Diffusion Models#3D Gaussian Splatting#VAE Latent Space#Anomaly Detection

圖像生成擴散模型(Diffusion)高斯噪聲調度、變分自編碼器(VAE)潛空間以及3D高斯潑濺(3DGS)的核心公式。

const normalPDF = (x, mu, sig) => Math.exp(-0.5 * ((x - mu) / sig) ** 2) / (sig * Math.sqrt(2 * Math.PI));
#Mini-Batch SGD#Monte Carlo Ray Tracing#Confidence Intervals#Statistical Inference

解釋小批量隨機梯度下降(Mini-Batch SGD)的 1/√n 方差縮減規律以及蒙特卡洛光線追蹤誤差界。

const stdError = (sigma, n) => sigma / Math.sqrt(n); const ci95 = (mean, se) => [mean - 1.96*se, mean + 1.96*se];
#Linear Regression#Supervised ML#Quant Finance Beta#Feature Engineering

機器學習監督學習線性回歸預測器、量化金融投資組合Beta係數以及特徵相關性分析的基石。

const slope = covXY / varX; const intercept = meanY - slope * meanX; const r = covXY / Math.sqrt(varX * varY);
#Cross-Entropy Loss#LLM Pretraining#Information Theory#KL Divergence

大語言模型(LLM)訓練、圖像分類器等幾乎所有現代分類與生成式AI的標準損失函數(Cross-Entropy Loss)。

const bceLoss = (y, yHat) => -(y * Math.log(yHat + 1e-9) + (1 - y) * Math.log(1 - yHat + 1e-9));
#Transformer Attention#Deep Learning Optimizer#LLM Temperature#Backpropagation

Transformer自注意力機制、LLM溫度採樣以及所有深度學習優化器(SGD, AdamW)的心臟公式。

const softmax = (zs, T=1) => { const exps = zs.map(z => Math.exp(z/T)); const s = exps.reduce((a,b)=>a+b,0); return exps.map(e => e/s); };