Assignment 6

Corresponds to: Session 6

Quiz: File Handling in Python (Text and Binary)

Course: Python for Structural Engineers
Topic: Reading and Writing Files with Context Managers
Time Allotted: 15 Minutes

Instructions

Select the most appropriate answer for each of the following questions.

1. What is the primary advantage of using the with statement (context manager) when opening a file in Python?
A. It makes the file reading process significantly faster.
B. It automatically closes the file, even if an exception/error occurs during processing.
C. It allows you to open multiple files simultaneously in different threads.
D. It encrypts the data being written to the disk.

2. You are working with a CSV file containing structural load data. Which mode should you use if you want to read the file without the risk of accidentally modifying it?
A. "w"
B. "a"
C. "r"
D. "wb"

3. You need to append a new set of sensor readings to the end of an existing log file without deleting the previous data. Which mode is correct?
A. "w"
B. "a"
C. "r+"
D. "rb"

4. What is the difference between 'r' and 'rb' modes?
A. 'r' is for reading files; 'rb' is for writing binary files.
B. 'r' is for reading text files; 'rb' is for reading files in binary format (e.g., images or compiled data)
C. 'r' is faster than 'rb'.
D. There is no difference; they are interchangeable.

5. When using f.readlines() on a text file, what is the data type of the returned object?
A. A single long string containing all the text.
B. A list of strings, where each element represents one line.
C. A dictionary where keys are line numbers.
D. A tuple of bytes.

6. If you are processing a massive structural analysis log file (e.g., 10 GB) and want to avoid crashing your computer's RAM, which approach is most memory-efficient?
A. data = f.read()
B. lines = f.readlines()
C. for line in f:
D. data = f.read().split('\n')

7. Which of the following code snippets will result in an error if the file results.txt does not exist?
A. with open('results.txt', 'w') as f:
B. with open('results.txt', 'a') as f:
C. with open('results.txt', 'r') as f:
D. with open('results.txt', 'wb') as f:

8. When writing a list of strings, such as ['Node 1\n', 'Node 2\n'], to a file, which method is specifically designed to handle an iterable of strings?
A. f.write()
B. f.writelines()
C. f.append()
D. f.save()

9. You are reading a text file that contains special mathematical symbols or non-ASCII characters (like the degree symbol °). Which parameter should you include in the open() function to ensure correct interpretation?
A. format='utf-8'
B. mode='binary'
C. encoding='utf-8'
D. type='unicode'

10. When opening a file in binary mode ('wb'), what type of data must be passed to the f.write() method?
A. A standard string.
B. An integer or float.
C. A bytes-like object (e.g., bytes or bytearray).
D. A list of characters.

11. A binary file is often described as being "non-human readable." What does this primarily mean in the context of Python?
A. Python cannot open the file.
B. The file does not follow standard text encoding (like UTF-8. and represents data as a sequence of raw 8-bit integers)
C. The file is encrypted and requires a password.
D. The file can only be opened by specialized engineering software.

12. In structural health monitoring, you receive a binary file where every 8 bytes represents a 64-bit floating-point number (a "double"). Which Python module is most commonly used to convert these raw bytes into actual Python float objects?
A. math
B. struct
C. numpy (though struct is the standard built-in for this)
D. Both B and C are correct.

13. When a file is opened in binary mode ('rb'), what is the data type of the object returned by the .read() method? A. str (String)
B. list (List of characters)
C. bytes
D. int (Integer)

14. You are reading a binary file containing raw sensor data. You only want to read the first 16 bytes to check the file header. Which command is correct?
A. f.read(16)
B. f.readline(16)
C. f.read_bytes(16)
D. `f.next(16)

15. When using the struct.unpack() method to parse binary data, what does the "format string" (e.g., '<f' or 'd') define?
A. The filename of the data.
B. The compression level of the file.
C. The data type (e.g., float, integer) and the byte order (endianness).
D. The number of lines in the file.

Quiz: Introduction to NumPy and Array Creation

Course: Python for Structural Engineers
Topic: NumPy Basics, ndarray, and Dimensionality (1D, 2D, 3D)
Time Allotted: 20 Minutes

Instructions

Select the most appropriate answer for each of the following questions.

1. What is the primary purpose of the NumPy library in the Python ecosystem?
A. To create graphical user interfaces (GUIs) for engineering software.
B. To provide high-performance multi-dimensional array objects and tools for working with these arrays.
C. To manage databases containing structural inspection records.
D. To automate the sending of emails and reports.

2. Why is NumPy preferred over standard Python lists for large-scale structural calculations (e.g., Finite Element Analysis)?
A. NumPy arrays are more flexible and can hold different data types (strings and floats) in the same array.
B. NumPy arrays are stored in a way that allows for much faster mathematical operations and better memory efficiency.
C. Python lists cannot perform addition or subtraction.
D. NumPy is the only library that allows for the use of loops.

3. What is the name of the core data structure in NumPy?
A. list
B. matrix_object
C. ndarray (N-dimensional array)
D. array_structure

4. Which of the following is the standard, community-accepted way to import NumPy?
A. import numpy
B. from numpy import *
C. import numpy as np
D. import numpy as n

5. You want to represent a simple set of 5 sensor readings as a 1D array. Which code snippet is correct?
A. arr = np.array([10.5, 12.1, 11.8, 13.0, 12.5])
B. arr = np.array(10.5, 12.1, 11.8, 13.0, 12.5)
C. arr = np.array([ [10.5, 12.1], [11.8, 13.0] ])
D. arr = np.array{10.5, 12.1, 11.8, 13.0, 12.5}

6. In structural engineering, a stiffness matrix is typically represented as a 2D array. How is a \(2 \times 2\) matrix represented using np.array()?
A. np.array([1, 2, 3, 4])
B. np.array([[1, 2], [3, 4]])
C. np.array([1, 2], [3, 4])
D. np.array([[1, 2, 3, 4]])

7. If you have a 2D array representing a table of data (rows and columns), what does the .ndim attribute tell you?
A. The total number of elements in the array.
B. The size of each dimension (e.g., 3 rows, 4 columns).
C. The number of dimensions (e.g., 2 for a matrix).
D. The data type of the elements (e.g., float64).

8. You are working with a 3D array (for example, a volumetric stress distribution in a 3D cube). Which of the following best describes the structure of the input list required for np.array()?
A. A single list of numbers.
B. A list of lists (a 2D structure).
C. A list of lists of lists (nested layers).
D. A dictionary containing lists.

9. Consider the following code: arr = np.array([[1, 2, 3], [4, 5, 6]]). What is the result of arr.shape?
A. (2,)
B. (3,)
C. (2, 3)
D. (6,)

10. Unlike Python lists, NumPy arrays are "homogeneous." What does this mean?
A. All elements in the array must be of the same data type (e.g., all floats).
B. The array can only contain integers.
C. The array size cannot be changed once created.
D. The array only works with positive numbers.