Question 8 (Advanced):
What is the time complexity of checking if an element exists in a Python set?

A) O(1)
B) O(n)
C) O(log n)
D) O(n^2)

#Python #DataStructures #TimeComplexity #Advanced

✅ By: https://yangx.top/DataScienceQ

Question 9 (Intermediate):
In SciPy, which function is used to solve ordinary differential equations (ODEs)?

A) scipy.optimize.minimize()
B) scipy.integrate.solve_ivp()
C) scipy.signal.lfilter()
D) scipy.linalg.solve()

#Python #SciPy #NumericalMethods #ODEs

✅ By: https://yangx.top/DataScienceQ

Question 10 (Advanced):
In the Transformer architecture (PyTorch), what is the purpose of masked multi-head attention in the decoder?

A) To prevent the model from peeking at future tokens during training
B) To reduce GPU memory usage
C) To handle variable-length input sequences
D) To normalize gradient updates

#Python #Transformers #DeepLearning #NLP #AI

✅ By: https://yangx.top/DataScienceQ

Question 11 (Expert):
In Vision Transformers (ViT), how are image patches typically converted into input tokens for the transformer encoder?

A) Raw pixel values are used directly
B) Each patch is flattened and linearly projected
C) Patches are processed through a CNN first
D) Edge detection is applied before projection

#Python #ViT #ComputerVision #DeepLearning #Transformers

✅ By: https://yangx.top/DataScienceQ

Question 12 (Intermediate):
What is the key difference between @classmethod and @staticmethod in Python OOP?

A) Classmethods can modify class state, staticmethods can't
B) Staticmethods are inherited, classmethods aren't
C) Classmethods receive implicit first argument (cls), staticmethods receive no special first argument
D) Classmethods are faster to execute

#Python #OOP #ClassMethod #StaticMethod

✅ By: https://yangx.top/DataScienceQ

Question 13 (Intermediate):
In NumPy, what is the difference between np.array([1, 2, 3]) and np.array([[1, 2, 3]])?

A) The first is a 1D array, the second is a 2D row vector
B) The first is faster to compute
C) The second automatically transposes the data
D) They are identical in memory usage

#Python #NumPy #Arrays #DataScience

✅ By: https://yangx.top/DataScienceQ

Question 1 (Advanced):
When using Python's multiprocessing module, why is if __name__ == '__main__': required for Windows but often optional for Linux/macOS?

A) Windows lacks proper fork() implementation
B) Linux handles memory management differently
C) macOS has better garbage collection
D) Windows requires explicit process naming

#Python #Multiprocessing #ParallelComputing #Advanced

✅ By: https://yangx.top/DataScienceQ

Question 2 (Expert):
In Python's GIL (Global Interpreter Lock), what is the primary reason it allows only one thread to execute Python bytecode at a time, even on multi-core systems?

A) To prevent race conditions in memory management
B) To simplify the CPython implementation
C) To reduce power consumption
D) To improve single-thread performance

#Python #GIL #Concurrency #CPython

✅ By: https://yangx.top/DataScienceQ

Question 3 (Intermediate):
In Tkinter, what is the correct way to make a widget expand to fill available space in its parent container?

A) widget.pack(expand=True)
B) widget.grid(sticky='nsew')
C) widget.place(relwidth=1.0)
D) All of the above

#Python #Tkinter #GUI #Widgets

✅ By: https://yangx.top/DataScienceQ

Question 4 (Intermediate):
In scikit-learn's KMeans implementation, what is the purpose of the n_init parameter?

A) Number of initial centroid configurations to try
B) Number of iterations for each run
C) Number of features to initialize
D) Number of CPU cores to use

#Python #KMeans #Clustering #MachineLearning

✅ By: https://yangx.top/DataScienceQ

Question 20 (Beginner):
What is the output of this Python code?

x = [1, 2, 3]
y = x
y.append(4)
print(x)

A) [1, 2, 3]
B) [1, 2, 3, 4]
C) [4, 3, 2, 1]
D) Raises an error

#Python #Lists #Variables #Beginner

✅ By: https://yangx.top/DataScienceQ

✅ **Correct answer: B) `[1, 2, 3, 4]`**

*Explanation:
- `y = x` creates a reference to the same list object
- Modifying `y` affects `x` because they point to the same memory location
- To create an independent copy, use y = x.copy() or y = list(x)*