PPolySim OS
Data & Statistics Pack · Multi-Solver

Time-Series Forecaster

Regress, Fourier, Kalman. This multi-solver chains 4 solvers into a single guided workflow — run each step in order and carry the result forward.

Workflow steps
  1. linear-regression
  2. fourier
  3. kalman-filter
  4. monte-carlo
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1

Linear Regression

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Linear RegressionLive

Controls

Presets

Ordinary least squares finds the line that minimizes the sum of squared vertical residuals (the gray drop-lines). R² measures the fraction of variance the line explains — 1 is perfect, 0 is useless. Add noise or remove points to watch the fit and R² degrade.

▶ Run in Python

Data Inspector

Fitted slope0.000
Intercept0.000
0.000
Correlation r0.000

Governing equation

Reading this result: R² = 0.00: noise (2) swamps the signal, so least squares can barely tell the slope from flat — adding data points would tighten the estimate.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

Fourier Series BuilderLive

Controls

Add harmonics and watch sine waves sum into a square, sawtooth, or triangle wave — the Fourier series in action.

Presets

▶ Run in Python

Data Inspector

Wavesquare
Harmonics8
Basissine

Governing equation

Reading this result: Reconstructing the square wave from 8 sine harmonics. More harmonics sharpen the reconstruction and pull it closer to the ideal shape. But at each discontinuity the Gibbs phenomenon leaves a persistent ~9% overshoot spike — adding terms only narrows that ripple, it never removes it, no matter how many harmonics you sum.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

3

Kalman Filter

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Kalman FilterLive

Controls

Presets

The Kalman filter fuses a motion model with noisy measurements to track a hidden state optimally. Each step it predicts, then corrects using the Kalman gain — trusting the measurement more when the model is uncertain, and vice versa. It smooths the jittery sensor (gray) into a clean estimate (cyan) that hugs the truth. The math behind GPS, radar, and spacecraft navigation.

▶ Run in Python

Data Inspector

Measurement RMSE0.0
Kalman RMSE0.0
Noise reductionNaN%

Governing equation

Reading this result: Measurement noise dwarfs process noise, so the Kalman gain stays small — the filter leans on its motion model and smooths the jitter hard.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

Monte Carlo Price SimulationLive

Controls

Presets

Geometric Brownian motion models a price with constant drift and random volatility — the assumption behind Black-Scholes. Running hundreds of simulated paths reveals the full distribution of outcomes, not just an average. Educational tool, not investment advice.

▶ Run in Python

Data Inspector

Median outcome$0
5th percentile$0
95th percentile$0

Governing equation

Reading this result: Median outcome is about $0, just under the drift-only $107 — GBM compounds in log-space, so volatility always pulls the typical path below the average.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Frequently asked questions

What is the Time-Series Forecaster multi-solver?
Time-Series Forecaster is a guided workflow that chains 4 individual PolySim solvers into one end-to-end analysis, piping each result into the next step.
Is it free to use?
Yes. Every step runs entirely in your browser using real numerics — no install, no account, no cloud cost. Custom or private solver packs are available as a paid service.