Script Execution Flow
Relevant source files
The following files were used as context for generating this wiki page:
Introduction
The script execution flow in this project focuses on the ingestion of clinical or biological data from text files and the subsequent application of statistical analysis. The primary objective is to automate the calculation of central tendency, dispersion, and distribution characteristics for datasets such as cholesterol levels and body weights.
The system utilizes standard Python libraries including numpy for numerical operations and statistics for specialized statistical measures. The flow is designed as a linear pipeline: file discovery, data sanitization, and metric computation.
Sources: hw1/p1.py:1-60, hw1/CHOLESTEROL.txt
Data Ingestion and Parsing
The execution begins by targeting specific flat-file databases. The script employs a robust reading mechanism to handle potential formatting inconsistencies within the source files.
File Loading Logic
The open_file function serves as the entry point for data. It iterates through each line of a provided filename, stripping whitespace and validating that the content is numeric before appending it to a global data structure.
The diagram illustrates the internal logic of the file parser, showing how non-numeric values are caught and skipped to prevent script termination.
Sources: hw1/p1.py:6-16
Statistical Computation Pipeline
Once data is loaded into the data list, the compute_file function orchestrates the calculation of eight distinct statistical metrics.
Computed Metrics Summary
| Metric | Library/Method | Description |
|---|---|---|
| Mean | np.mean | Arithmetic average of the dataset. |
| Median | np.median | Middle value of the sorted data. |
| Mode | statistics.mode | Most frequently occurring value. |
| Range | np.ptp | Peak-to-peak difference (Max - Min). |
| Std Deviation | np.std | Measure of data dispersion. |
| Variance | np.var | Squared deviation from the mean. |
| CV 1 | Pearson's Formula | $3 * (Mean - Median) / Std$ |
| CV 2 | Skewness Formula | Third moment calculation for distribution shape. |
Sources: hw1/p1.py:22-54
Computational Flow
The following sequence diagram outlines the interaction between the main script execution, the helper functions, and the external libraries.
Sources: hw1/p1.py:18-60
Data Structures and Global State
The script maintains a global list named data to store processed numeric values. This list is populated during the open_file phase and subsequently accessed by the numpy and statistics functions during the analysis phase.
data(list): A dynamic array of floating-point numbers derived from files likeWEIGHT.txtorCHOLESTEROL.txt.- Source Data Format: Files contain single numeric values per line, often with trailing whitespace or empty lines.
Sources: hw1/p1.py:5, hw1/WEIGHT.txt, hw1/CHOLESTEROL.txt
Conclusion
The script execution flow provides a structured approach to univariate statistical analysis. By separating file I/O from mathematical computation, the system ensures that data is cleaned before being processed by the NumPy engine, resulting in accurate measures of central tendency and variation for the provided biological datasets.