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Curve Fitting — Nonlinear Regression

Prism-style curve fitting with Levenberg-Marquardt optimization. 9 models including dose-response, enzyme kinetics, and more.

Equation: Y = Bottom + (Top - Bottom) / (1 + 10^((LogEC₅₀ - X)·Hill)) |  Parameters: Bottom, Top, LogEC₅₀, HillSlope

Examples:

4-Parameter Logistic (Dose-Response)

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📊 Data Input

💡 Tip: Paste directly from Excel or Google Sheets (Ctrl+V / ⌘V)

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📖 Available Models (GraphPad Prism-style)

Linear Regression: Y = a + b·X
Quadratic (2nd Order Polynomial): Y = a + b·X + c·X²
Cubic (3rd Order Polynomial): Y = a + b·X + c·X² + d·X³
Exponential Growth: Y = Y₀ · exp(k·X)
Exponential Decay (one-phase): Y = (Y₀ - Plateau) · exp(-k·X) + Plateau
4-Parameter Logistic (Dose-Response): Y = Bottom + (Top - Bottom) / (1 + 10^((LogEC₅₀ - X)·Hill))
Michaelis-Menten: Y = Vmax · X / (Km + X)
Gaussian (Bell Curve): Y = Amp · exp(-(X - μ)² / (2σ²))
Power (Allometric): Y = a · X^b
Hill Equation (Cooperative Binding): Y = Bmax · X^n / (Kd^n + X^n)