Challenge: "Cosmic Signal Decoder"

Concept: You’re an interstellar hacker decoding a mysterious signal from a distant galaxy. The signal is a string of numbers and letters, and your job is to write a Python script to extract a hidden message, analyze its patterns, and visualize the results—all in under an hour.

Why it's optimized for devs:

• Coding & Creativity
• Data Analysis
• Portfolio Boost
• Time-Boxed

The Signal: Here's the raw signal you've intercepted:

signal = "3K7P9Q2R8T4M1N6J5H2G8F4D9C1B7A2Z4Y6X8W3V5U9T2S1R7Q4P3N6M8L2K9J4H5G1F7D3C8B2A6Z9Y4X5W3V8U2T1R7Q6P4N3M9L2K8J5H4G1F7D"

It's a mix of numbers (0-9) and letters (A-Z). The hidden message is encoded in the letters but you need to filter and decode it based on a rule.

The Mission:

1. Extract the Message (15 min):

   • Write a function to filter out numbers and keep only letters (A-Z).
   • The letters form a sequence, but every third letter is part of the actual message. Concatenate those to reveal the hidden text.
   • Hint: Use string methods or regex to clean the signal, then slice or loop to grab every third letter.

2. Analyze the Signal (15 min):

   • Convert the numbers in the signal to a list of integers.
   • Calculate basic stats: mean, median, and standard deviation (use NumPy or Pandas).
   • Count how many times each letter appears in the full signal (use a dictionary or Pandas).

3. Visualize It (10 min):

   • Create a quick plot with Matplotlib: a bar chart of letter frequencies.

   • Save the plot as cosmic_signal.png for your portfolio.

     

4. Stretch Goal (if time allows):

   • Check if the numeric sequence has any patterns (e.g., is it random, or does it follow a simple rule like alternating odd/even?). Print a one-sentence hypothesis.