Teach Cloud - Cloud, DevOps, and Python Backend Development Blog

❓ Quiz Question

Oct 25, 2026

Quiz: What occurs in memory when you slice a NumPy array (e.g., `b = a[1:5]`) versus boolean indexing (`c = a[a > 0]`)?

Basic slicing returns a view sharing the original array buffer; fancy/boolean indexing creates a brand new copy .

#Scientific Python & PyData #Quiz #Interactive

❓ Quiz Question

Oct 25, 2026

Passing -1 signals NumPy to dynamically compute that dimension based on the total elements and specified dimensions.

#Scientific Python & PyData #Quiz #Interactive

❓ Quiz Question

Oct 25, 2026

A Series is a 1D labeled array capable of holding any data type; a DataFrame is a 2D tabular structure aligned by index and columns.

#Scientific Python & PyData #Quiz #Interactive

❓ Quiz Question

Oct 25, 2026

.loc[] indexes by index/column labels and includes the stop slice; .iloc[] indexes by 0-based integer positions and excludes the stop slice.

#Scientific Python & PyData #Quiz #Interactive

❓ Quiz Question

Oct 25, 2026

df.fillna() fills NaN values using a specified scalar, dictionary, or imputation strategy (e.g. forward/back fill).

#Scientific Python & PyData #Quiz #Interactive

❓ Quiz Question

Oct 25, 2026

df.groupby('col').agg(['mean', 'max']) applies multiple aggregation functions across groups in a single efficient pass.

#Scientific Python & PyData #Quiz #Interactive

❓ Quiz Question

Oct 25, 2026

By default, pd.merge() performs an inner join unless specified otherwise with the how= parameter.

#Scientific Python & PyData #Quiz #Interactive

❓ Quiz Question

Oct 25, 2026

Converting low-cardinality strings to category stores an internal integer lookup table with unique categories, reducing memory by up to 90%.

#Scientific Python & PyData #Quiz #Interactive