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Don't know what to learn? Good.
Follow your curiosity.
5471 connected concepts. Watch ideas unfold, predict what happens, change one thing — then go deeper.
Try one:
- Where does each argument in the braced list go, and which one is the function the thread runs?
- When the caller reaches join(), does it keep running, and under what condition does it proceed past that call?
- How does comparing two values transform them into a single boolean result?
- How does Python evaluate a chained comparison such as 0 <= score <= 100?
- How can parentheses make the intended evaluation structure visible in a mixed logical expression?
- How does one piece of code process different subtype objects without checking each object's specific type?
01 · Surprise meBored?
Bored?
Pick something random.
Bored?
Let the Atlas pick something for you.
One click, one idea you probably haven't looked at yet.
02 · See how it works
Pick an idea. Watch it unfold.
How does it work?
Where Each Constructor Argument Goes
Where does each argument in the braced list go, and which one is the function the thread runs?
Step 1 / 5Braced argument list
Also explore
Playground · Play with it
Don't read it. Run it.
- Rank pages by their linksPageRank
- Push, pop, enqueue, dequeueStack and Queue
- Move the file pointerReading and Writing Text Files
- Break a constraint on purposeKeys and Constraints
- Send a request, read the responseHTTP Request and Response
- Build an XML tree and query itXML Element Trees
- Flip bits and watch the number changeBinary Numbers and Bits
- Train a logistic regression and move its thresholdLogistic Regression
- Fit a small Sequential model and watch validation loss turnTraining a Keras-Style Model: History and Early Stopping
- Turn a sentence into ids and vectorsText Vectorization: Tokens to Vectors
- Drag the bars and watch E[X] moveExpectation and Variance of a Random Variable
03 · What happens if…
Guess first. Then find out.
Predict it
When is a type function evaluated?
Predict it
If a function never uses return to send anything back, how could the code that called it still get a result?
Predict it
If epsilon is set to exactly zero for one latent dimension, what value does z take, given the formula z = z_mean + exp(z_log_variance / 2) times epsilon?
Predict it
If a holds {1, 2, 3} and b holds {10, 20, 30}, what does c = a + b contain?
04 · Change one thing
Change one thing. See what changes.
Tracing a Value into a Variable
double value = 3.7;
int count = value;Before: The equals-sign form places the fractional value into an int variable.
Your turn. Edit a value and press Run — real Python, right in your browser. From Conditional Logic in Python.
python
Output (expected)
20240115
143025_evening_files.zip05 · Rabbit hole
Fall down a rabbit hole.
Each idea leads to the next — follow the links the Atlas itself draws between concepts.
06 · Concept battles
Both explained in Binding Function Arguments with std::bind →
Both explained in Types and Type Systems →
Both explained in Concurrent Programming with Tasks and Threads →
Both explained in Conditional Logic in Python →
Both explained in Returning Results From Threads →
Both explained in Data Types and Type Conversion →
This vs that.
EnginevsDistribution
| What is its job? | Source of randomness | Maps engine output to a specific range |
|---|---|---|
| What does it produce? | Raw values from its own output range | Values within the range it was configured with, such as 1 to 6 |
| Which name in the die example? | re | one_to_six |
Type takes a type as argumentvsType returns a type
| Where does the type sit? | On the input side of the function | On the output side of the function |
|---|---|---|
| What flows in? | A type | Something other than the result type |
| What comes out? | Something other than necessarily a type | A type |
What it doesvsWhat it does not do
| start() on a thread | Sets the thread's work running alongside the rest of the program | Does not tell the program when that work is finished |
|---|---|---|
| join() on a thread | Pauses the caller until that thread has terminated | Does not start the thread, perform its work, stop it, or cancel it |
| Code placed after join() | Runs once the joined thread has terminated | Is not guaranteed to be safe to run before the join |
C or C++ switchvsPython if..elif..else
| Branch selection | Cases compare against a switch expression | Conditions are checked in order |
|---|---|---|
| Default behavior | default handles unmatched cases | else handles unmatched conditions |
| Multiple branch execution | Can fall through when break is omitted | Only one branch executes |
Plain function fvsFunction object F{vec2}
| What is written in the constructor | The function name f | An object F that stores vec2 and defines an operator |
|---|---|---|
| Where the vector comes from | Passed in as an argument, wrapped with ref() | Stored as a reference inside the object |
| What the compiler builds | A function object for the thread to execute | A function object for the thread to execute |
What the source saysvsImportant detail
| Numbers | Numbers are one of the basic types. | They are values that Python treats as numbers. |
|---|---|---|
| Strings | Strings are one of the basic types. | They are values that Python treats as strings. |
| Lists | A list contains items enclosed in square brackets. | A list can be altered by adding or removing items, so it is mutable. |
07 · Atlas is growing
New in the Atlas.
- Abstraction and Resource Management in C++C++ lets programmers define user-defined types, which model their own ideas as named types in a program
- Accessing List Elements by IndexLists are mutable: you can change their contents after creation by reassigning elements using bracket notation on the left side of an assignment.
- Asynchronous Task Execution with async()Task-based parallelism treats each task as a function that may run concurrently with other tasks.
- Atomics and Lock-Free ProgrammingWork at the highest level of abstraction that you can afford in concurrent programming.
- C++98 and the First ISO StandardC++11, known for years as C++0x, was produced by the WG21 committee and ratified by a 21-0 national vote in August 2011 as the second ISO C++ standard.
- C++ Evolution and StandardizationA language standard does not reliably finish on the schedule its early planning suggests; the source explicitly notes that overly optimistic completion dates are common in large projects.
08 · Build your path
Where do you want to end up?
Pick a destination and see the exact chapters you'd walk through.
- 1Getting StartedGetting Started
- 2Discovering PythonThe Story Behind Python · Key Features of Python · Summary and Version Differences
- 3Installing Python on Your SystemInstalling Python on Windows · Verifying Python Installation on Mac OS X and GNU/Linux
- 4Getting Started with Python ProgrammingUsing the Python Interpreter Prompt · Choosing an Editor for Python Programming · Writing and Running Python Programs using Source Files · +1 more
- 5Python BasicsComments and Literal Constants · Numbers and Strings · Variables and Identifiers · +3 more
- 6Understanding Operators and Expressions in PythonIntroduction to Operators · Shortcut for Math Operations and Assignment · Evaluation Order and Precedence · +1 more
- 7Mastering Control Flow in PythonConditional Statements · Loops in Python · Controlling Loop Execution
- 8Mastering Functions in PythonDefining and Calling Functions · Function Parameters and Arguments · Local Variables and Scope · +4 more
- +7 more chapters
09 · For you
Go deeper.
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