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Python and NumPy

Replay a recorded greenhouse sample

BOTIE

Gather the readings at the supplied zero-based indices, then return the mean of that selected list.
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Context for this challenge

Gather the readings at the supplied zero-based indices, then return the mean of that selected list.

Botie recorded the chosen indices from a resample. Replaying those choices must retain observations selected more than once.

Gather the original readings at the saved indices, then calculate the mean of that gathered list.

Examples and results
Original greenhouse readings
  1. 010
  2. 120
  3. 230
  4. 340
Recorded sample indices
  1. 01
  2. 11
  3. 23
Required result
26.6667
Original greenhouse readings
  1. 05
  2. 115
  3. 225
Recorded sample indices
  1. 02
Required result
25
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Assumptions and test precision

The indices are supplied. This construction does not generate randomness or establish that a sample is representative. Numerical tests allow a difference of 0.001. Lists and structures must also have the right shape.

One reading is drawn three times

This check uses the pieces from “Replay the sample before averaging it”.

BOTIE

Replay the supplied draw, where the first reading appears three times and the last appears once. Predict the sample mean without deduplicating the indices.
Original greenhouse readings
  1. 02
  2. 18
  3. 214
Recorded sample indices
  1. 00
  2. 10
  3. 20
  4. 32

Use a number, text, or an array matching the requested result. For a matrix, put each row in brackets. Saving your prediction runs your current construction on these inputs and checks the earlier examples too.

Build a construction in the workspace above first. This case will test those pieces.

What must be retained alongside the original readings to replay this result, and what does replaying fail to establish about representativeness?

A saved sample specification supports reproducibility; it does not by itself justify a sampling design.

The indices are supplied. This construction does not generate randomness or establish that a sample is representative.

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