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Ok-landscape
GitHub Repository: Ok-landscape/computational-pipeline
Path: blob/main/notebooks/published/bisection_method/bisection_method_posts.txt
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# Social Media Posts: Bisection Method for Root Finding
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## SHORT-FORM POSTS
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### Twitter/X (280 chars)
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The bisection method: when in doubt, split it in half!
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Finding where f(x) = x³ - x - 2 crosses zero:
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→ Start with [1, 2]
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→ 37 iterations later: x ≈ 1.521379706804568
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Simple, robust, guaranteed to work.
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#Python #NumericalMethods #Math
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### Bluesky (300 chars)
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Implemented the bisection method for root finding today.
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Given f(x) = x³ - x - 2 on [1, 2]:
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• Error halves each iteration: εₙ = (b₀ - a₀)/2ⁿ⁺¹
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• Found root x ≈ 1.521379706804568 in 37 iterations
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• Linear convergence, but guaranteed to work for any continuous function
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### Threads (500 chars)
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Ever need to find where a function equals zero? The bisection method is your reliable friend.
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Here's how it works:
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1. Pick an interval [a, b] where f(a) and f(b) have opposite signs
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2. Check the midpoint c = (a + b)/2
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3. Narrow down to whichever half contains the root
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4. Repeat until you're close enough
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For f(x) = x³ - x - 2, starting from [1, 2]:
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→ 37 iterations
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→ Root: x ≈ 1.521379706804568
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→ Error bound: 10⁻¹⁰
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Not the fastest method, but it ALWAYS works. That's the beauty of it.
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### Mastodon (500 chars)
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Exploring the bisection method for root finding.
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For a continuous f(x) with f(a)·f(b) < 0, the Intermediate Value Theorem guarantees a root in (a, b).
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Algorithm:
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• Compute midpoint: c = (a + b)/2
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• Update interval based on sign of f(c)
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• Error after n iterations: |r - cₙ| ≤ (b₀ - a₀)/2ⁿ⁺¹
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Results for f(x) = x³ - x - 2 on [1, 2]:
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• Root: 1.521379706804568
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• 37 iterations for ε = 10⁻¹⁰
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• Linear convergence (rate = 1/2)
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Also found the Dottie number solving cos(x) - x = 0!
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#NumericalAnalysis #Python #Mathematics
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## LONG-FORM POSTS
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### Reddit (r/learnpython or r/math)
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**Title:** Visualizing the Bisection Method: A Simple but Powerful Root-Finding Algorithm
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**Body:**
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I created a Jupyter notebook exploring the bisection method, one of the most fundamental algorithms in numerical analysis. Here's what I learned:
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**The Basic Idea (ELI5)**
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Imagine you're playing a number guessing game. Someone picks a number between 1 and 100, and tells you "higher" or "lower" after each guess. The optimal strategy? Always guess the middle.
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That's exactly what the bisection method does for finding roots (where a function equals zero).
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**How It Works**
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1. Start with an interval [a, b] where f(a) and f(b) have opposite signs
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2. The Intermediate Value Theorem guarantees a root exists between them
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3. Compute the midpoint c = (a + b)/2
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4. Check which half contains the root (based on sign of f(c))
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5. Repeat with the new, smaller interval
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**Key Results**
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For f(x) = x³ - x - 2 on [1, 2]:
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- Found root x ≈ 1.521379706804568
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- Required 37 iterations for tolerance 10⁻¹⁰
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- Error bound after n iterations: (b₀ - a₀)/2ⁿ⁺¹
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**Why It Matters**
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The bisection method has LINEAR convergence (error halves each step), which is slower than Newton-Raphson's quadratic convergence. But here's the tradeoff:
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✓ Guaranteed to converge for continuous functions
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✓ No derivatives needed
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✓ Numerically stable
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✗ Needs initial bracketing with sign change
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✗ Can't find tangent roots
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**Bonus:** Also found the Dottie number (≈0.739) by solving cos(x) - x = 0. It's the unique fixed point of cosine!
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Check out the full notebook with visualizations:
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https://cocalc.com/github/Ok-landscape/computational-pipeline/blob/main/notebooks/published/bisection_method.ipynb
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### Facebook (500 chars)
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Ever wondered how computers find exact solutions to equations?
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The bisection method is beautifully simple: keep cutting the search space in half until you find the answer.
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For the equation x³ - x - 2 = 0:
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• Start between 1 and 2
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• 37 halvings later → x ≈ 1.5214
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It's like a high-low guessing game, but for math! Slow but guaranteed to work.
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View the interactive notebook:
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https://cocalc.com/github/Ok-landscape/computational-pipeline/blob/main/notebooks/published/bisection_method.ipynb
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### LinkedIn (1000 chars)
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Exploring Numerical Methods: The Bisection Algorithm
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Just completed an implementation of the bisection method for root finding—a foundational algorithm in numerical analysis that demonstrates key principles of computational mathematics.
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**Technical Implementation:**
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• Python with NumPy/Matplotlib
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• Full iteration history tracking
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• Convergence visualization and error analysis
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**Key Findings:**
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For f(x) = x³ - x - 2 on interval [1, 2]:
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• Converged to x = 1.521379706804568 in 37 iterations
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• Achieved error bound of 10⁻¹⁰
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• Verified theoretical convergence: εₙ = (b₀ - a₀)/2ⁿ⁺¹
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**Why This Matters:**
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The bisection method offers guaranteed convergence for continuous functions—critical when reliability matters more than speed. It's often used to:
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• Provide initial estimates for faster algorithms (Newton-Raphson)
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• Solve problems where derivatives are unavailable
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• Handle functions with numerical instabilities
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**Skills Demonstrated:**
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• Numerical analysis theory and implementation
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• Scientific visualization
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• Algorithm convergence analysis
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Full notebook with interactive code:
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https://cocalc.com/github/Ok-landscape/computational-pipeline/blob/main/notebooks/published/bisection_method.ipynb
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#NumericalMethods #Python #DataScience #ComputationalMathematics #ScientificComputing
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### Instagram (500 chars)
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Finding where math meets zero
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The bisection method is elegant in its simplicity:
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→ Pick an interval
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→ Split in half
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→ Keep the half with the answer
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→ Repeat
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For x³ - x - 2 = 0:
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Starting interval: [1, 2]
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After 37 halvings: x ≈ 1.5214
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The error halves every single time.
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Guaranteed convergence.
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No fancy calculus required.
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Sometimes the simplest approach
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is the most reliable.
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Swipe to see the convergence plots →
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#NumericalMethods
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#Mathematics
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#Python
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#DataVisualization
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#CodingLife
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#STEM
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#ScienceIsBeautiful
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