# Wireline **by [Matt Hall](https://github.com/kwinkunks)** You have a 'log', a series of bulk density measurements from a borehole. There is a measurement every 0.1524 m, starting at the top of the borehole. The measurements have units of kg/m3 and look like this: 2193.5,2234.3,2270.2,2764.4,2781.8,2805.7,2794.3,2784.0,2057.9,2006.8,2007.1,2033.2 The log contains a number of geological 'beds' which have a very specific definition: neighbouring pairs of samples that differ by more than 100 kg/m3 constitute a bed boundary. These are bed boundaries. Any section of the log between two bed boundaries is a bed. If the boundaries are 5 samples apart, assume the bed is 5 × 0.1524 = 0.7620 m thick. Answer the following questions about your data. 1. How many samples are in your dataset? 2. Calculate the mean μ and standard deviation σ of the data. How many samples are greater than (μ + σ)? 3. How many beds are there? Include the first and last beds (those at the very top and bottom of the log). 4. How many beds are thicker than 10 m? ## Example For the short example data above, the questions would be answered as follows: 1. There are **12** samples in the dataset. 2. μ is 2394.4 and σ is 340.74, so **5** samples are greater than (μ + σ). 3. There are **3** beds in the data, with densities of about 2200, 2800, and 2000 kg/m3 respectively. 4. The bed thicknesses are 0.4572, 0.7620, and 0.6096 m respectively, so **0** of these beds are thicker than 10 m. ## A quick reminder how this works This document is formatted in [Markdown](https://daringfireball.net/projects/markdown/). You can retrieve your data, which is always a string, by choosing a **``** (also a string). This ensures that you have different data from other people, so be creative. ``` url = 'https://kata.scienxlab.org/challenge/wireline' params = { 'key': # Replace with your own string. } r = requests.get(url, params) r.text ``` To answer question 1, change the `params`: ``` params = { 'key': , # Use the same key you used to get your input. 'question': 1, 'answer': 1234 # Your answer; can be a float, int, list or array; # the challenge description will tell you which. } ``` To get a hint for a question, provide the question number but no answer: ``` params = { 'question': 1, } ``` [Complete instructions at kata.scienxlab.org](https://kata.scienxlab.org/challenge) [An example notebook to get you started](https://gist.github.com/kwinkunks/50f11dac6ab7ff8c3e6c7b34536501a2) ---- © 2024 [Scienxlab](https://scienxlab.org/) — Code: openly licensed under [Apache 2.0](https://www.apache.org/licenses/LICENSE-2.0) — Text: openly licensed under [CC BY](https://creativecommons.org/licenses/by/4.0/).