Intermediate concepts in AI & ML, page 4
HTML Parsing: Turning Web Pages into Data
Think of HTML parsing as X-ray vision for web pages, revealing the underlying data structure. It's used for web scraping and automated testing. The main footgun is using regex; a real parser is robust against markup changes.
Conda Environments: Isolate Your Project Dependencies
Think of a Conda environment as a separate workshop for each project, with its own tools (packages) and Python version. This prevents dependency conflicts when Project A needs a different library version than Project B.
GraphQL Queries: Ask for Exactly What You Need
GraphQL lets clients ask for exactly the data they need in a single call, like a flexible SQL query for your API. It avoids the over-fetching of fixed REST endpoints, making apps faster. The footgun: complex client queries can overload your server.
ETL: The Three-Phase Data Pipeline
ETL is a three-phase pipeline: extract from sources, transform, and load into containers. It supports many sources and destinations and runs as automated software, manual jobs, or scheduled batches. The footgun is manual execution of recurring jobs.
Docker Bind Mounts: A Portal to Your Host Filesystem
A bind mount is a portal from your host machine's filesystem directly into a container, where changes on either side are reflected instantly. Use it for live code development, but never for production data, as it creates a major security risk.
Homography: Mapping Flat Surfaces Between Images
A homography is a 3x3 matrix that maps points between two images of a flat surface. It's used for panorama stitching and perspective correction. The footgun: it only works for planes or pure camera rotation, failing on scenes with depth.
Dev Containers: Your Dev Environment as Code
A dev container packages your entire development environment—tools, libraries, and settings—into a single, portable container. Use it to standardize team environments, simplify onboarding, and ensure consistency between local dev and CI.
PEFT: Fine-Tune Large Models on a Budget
Parameter-Efficient Fine-Tuning (PEFT) adapts huge models without retraining everything. It's like adding a task-specific cheat sheet to a genius brain. Use it to specialize LLMs on consumer GPUs.
Webhooks: Don't Call Us, We'll Call You
A webhook is an automated HTTP callback from a service to your app when an event happens. Instead of polling for updates, the service calls you. This is how Stripe signals a payment or GitHub a commit.
The Fundamental Matrix: Constraining 3D Search to a Line
The Fundamental Matrix reduces a 2D search for a point in a second image to a 1D search along a line. It's the geometric glue linking two uncalibrated camera views of the same scene, crucial for stereo vision and 3D reconstruction.
Configuration as Code: Version Control for Your Settings
Configuration as Code treats your system settings like source code: defined in files, versioned, and automatically applied. It's used to manage app settings or service credentials across environments, preventing manual errors.
Instruction Fine-Tuning: Teaching LLMs to Follow Orders
Instruction fine-tuning teaches a base LLM to follow commands, not just predict the next word. It turns a raw text-completion engine into a helpful assistant, enabling it to answer questions or summarize text. The footgun: it learns style, not facts.
robots.txt: The Web's 'Keep Off The Grass' Sign
robots.txt is a public file suggesting which parts of a site web crawlers shouldn't visit, like admin areas. The footgun: it's a polite request, not a security wall. Malicious bots will ignore it, so never use it to hide sensitive data.
The Essential Matrix: Geometry for Stereo Vision
The Essential Matrix is a geometric bridge between two photos of the same scene, encoding the camera's relative motion. It's used in 3D reconstruction to find corresponding points; it tells you where a point from one image must lie in the other.
Reward Modeling: Teaching an LLM What 'Good' Means
A reward model is a judge that scores an LLM's outputs based on human preferences. It learns to assign a numerical 'goodness' score to text, turning subjective quality into an optimizable signal for training models like ChatGPT.
Querying NoSQL: It Depends on the Data Model
Querying NoSQL isn't one-size-fits-all; the method depends on the data model (key-value, document, graph). This is used for large, unstructured datasets like social feeds. The footgun is assuming SQL works everywhere; many require a model-specific API.
Triangulation: Finding 3D Points from 2D Images
Like your two eyes judging distance, triangulation finds a point's 3D location by seeing it from two different 2D camera views. It's key for 3D reconstruction and robotics.
Structure from Motion (SfM): Rebuilding 3D from 2D Photos
Structure from Motion (SfM) reconstructs a 3D scene from 2D images taken from different viewpoints, much like your brain perceives depth. It's used for creating 3D maps from drone footage. The main footgun is its failure on textureless or reflective surfaces.
Parameter Servers for Distributed ML Training
A parameter server splits the work in distributed training: central servers hold the model's parameters, while worker nodes pull parameters, compute gradients on data subsets, and push updates back. This enables training models too large for one machine.
Horovod: Scale ML Training Across Many GPUs
Horovod scales a single-GPU training script to hundreds of GPUs with minimal code changes, slashing training time. It's used when models are too big for one machine.
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