Practice

Use a diagnostic to locate gaps, then open only the relevant topic practice.

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Diagnostics

Mathematics Diagnostic

Sample the four mathematics topics before choosing focused practice.

Mathematics · 6 items · 60 min

Programming Diagnostic

Check Python semantics, data-structure selection, algorithmic control flow, and recursion.

Programming · 5 items · 50 min

Machine Learning Diagnostic

Sample objectives, updates, model evaluation, representation, networks, and clustering.

Machine Learning · 8 items · 60 min

Topic practice

Linear Algebra Practice

Cover matrix fundamentals, subspaces, projections, spectral structure, and decomposition.

Mathematics · 9 items · 150 min

Calculus Practice

Cover single-variable foundations, multivariable differentiation, approximation, and optimization.

Mathematics · 8 items · 120 min

Probability Practice

Move from events and conditioning through moments, distributions, and asymptotic results.

Mathematics · 12 items · 130 min

Statistics Practice

Cover estimators, likelihood, Bayesian updating, intervals, tests, and simple regression.

Mathematics · 11 items · 130 min

Control Flow Practice

Build reliable branching, iteration, function, comprehension, and trace fluency.

Programming · 3 items · 35 min

Data Structures Practice

Select and use lists, mappings, sets, stacks, queues, heaps, and graph traversals.

Programming · 7 items · 90 min

Python Practice

Eliminate mistakes in slicing, sorting, mutability, aliasing, iteration, and complexity.

Programming · 5 items · 55 min

Recursion Practice

Practice base cases, call traces, and recursive decomposition.

Programming · 4 items · 45 min

Regression Practice

Connect squared loss, gradients, normal equations, and ridge regularization.

Machine Learning · 3 items · 35 min

Classification Practice

Connect logistic probabilities and losses to threshold-dependent evaluation.

Machine Learning · 4 items · 40 min

Convolution Practice

Compute convolution geometry and parameter counts accurately.

Machine Learning · 1 items · 20 min

Gradient Descent Practice

Compute deterministic and stochastic updates and diagnose step-size behavior.

Machine Learning · 3 items · 25 min

Neural Networks Practice

Practice forward computation, backpropagation, activation behavior, and parameter counting.

Machine Learning · 3 items · 35 min

Optimization Practice

Relate stationary points, convexity, objectives, regularization, and training diagnostics.

Machine Learning · 3 items · 30 min

Theory Practice

Reason about bias, variance, overfitting, generalization, and evaluation splits.

Machine Learning · 4 items · 25 min