e (2.71828)

Euler's number, e ≈ 2.71828, is one of those constants you never think about in ComfyUI - until you're building an exponential curve and realize you need to feed a node the literal value 2.71828, and you don't want to type it and get the rounding slightly wrong. The e node from Basic data handling just returns the constant, so you never have to.

This is a node with zero inputs. You drag it in, it hands you FLOAT = e, and you wire that number somewhere. It's about as minimal as a custom node gets.

Why a whole node for a number?

Fair question. The practical reasons are the ones that usually justify any constant node:

• Exactness. math.e is a full double-precision float, good to ~15 significant digits. If you type 2.718 into a value widget you're already 0.00028 off, and for exponential math that error compounds fast.
• Readability. A node named e sitting in your graph says "exponential involved here" more clearly than a bare number in a widget.
• The formula node quirk. The pack's MathFormula node treats e as a function - you write e() in the formula to get the constant, because a bare e is reserved for a variable input. This node gives you the same value as a plain wire, no parentheses involved.

Where does e actually get used in an image or video workflow? Exponential decay is the big one - smooth denoise ramps, noise-level falloff, scheduling curves where you want values that halve (or double) per step rather than shrink linearly. If you've ever hand-rolled a curve that looks right at the start and wrong at the end, exponential is probably what you were reaching for, and e is the base of it.

The mechanism

There's no real mechanism to explain. Under the hood the node returns math.e from Python's standard library. No calculation, no state, no model involved. It's the same value the MathExp node uses internally when you ask it for e^1.

Installing it

This is the whole package's install story, and it's refreshingly short: Basic data handling has no dependencies and downloads no models. Install via ComfyUI Manager (search "Basic data handling"), or:

cd ComfyUI/custom_nodes
git clone https://github.com/StableLlama/ComfyUI-basic_data_handling

Restart ComfyUI and you'll find e under Basic/maths.

Should you bother?

If you're building math-heavy automation - schedulers, decay curves, anything with growth - grab it, it's free. If you're doing plain text-to-image, you'll never open this node and that's fine too. It's a niche convenience, but it's a correctly-rounded one, which is more than you can say for the 2.718 you were about to type.