Sinus

If a downloaded workflow has a bare node called Sinus in it - no DF_ prefix - you're looking at an older fixture of Derfuu_ComfyUI_ModdedNodes, a math-and-utility pack that's been part of ComfyUI since 2023. It computes a sine, or with a toggle, an arcsine.

The pack also ships DF_Sinus, with identical inputs and output, in the same Derfuu_Nodes/Math/Trigonometry menu. The bare Sinus reads as the older, pre-DF_-prefix name kept around so existing workflows don't break, while the rest of the pack (DF_Sum, DF_Cosines, DF_Tangent, and so on) settled on the DF_ convention. If you're wiring something new, use DF_Sinus instead - same math, but the name that matches everything else in the pack.

How it works

Three inputs:

• value (FLOAT, default 1) - the angle to take the sine of, or, with arcSin on, the ratio you want the angle for.
• type_ - RAD or DEG, so the node works in whichever unit the rest of your math chain uses.
• arcSin - toggles the node between sine and its inverse, arcsine.

One output, a FLOAT: sin(value) with arcSin off - always between -1 and 1 no matter the input angle - or, with arcSin on, the angle that corresponds to a ratio you feed it, in radians or degrees depending on type_. Having both directions behind one toggle rather than as two separate nodes is a small, genuinely useful choice.

Nobody needs this for a standard image-generation workflow. It's for the minority of graphs where a value needs to follow a periodic curve instead of a straight line - staggering a parameter across a batch on a sine wave, or any hand-built math formula wired up before ComfyUI had a real expression node. If you know rgthree's Power Puter, that's the modern equivalent: one node, a typed formula, no per-operation wiring. Derfuu's approach predates it - one operation, one node, every intermediate value visible on the canvas.

How to install it

Grab the whole pack - there's no way to install a single node out of a repo like this. ComfyUI Manager: search Derfuu_ComfyUI_ModdedNodes, install, restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/Derfuu/Derfuu_ComfyUI_ModdedNodes

then restart. No models, no unusual dependencies - pure Python math, so the install itself is fast and rarely the source of trouble.

Common issues & troubleshooting

Node not visible right after installing. Restart the server and hard-refresh the browser tab - a stale frontend cache is the standard cause across basically any custom-node pack, not something specific to this one.

Result looks off by a factor related to units. Check type_ - mixing radians and degrees between this node and whatever set the value upstream is the usual cause of a sine result that "shouldn't" be what it is.

Worth knowing long-term: Derfuu has a track record of deleting deprecated nodes outright on updates instead of leaving a legacy-labeled copy in place - people who've depended on the pack for a while have specifically flagged this happening. If a workflow that used to load cleanly starts throwing a missing-node error after an update, that's the likely cause; check the pack's GitHub for a renamed equivalent before assuming your setup is broken. Trig nodes haven't historically been the ones pruned, but given that history, DF_Sinus - the current name - is the safer bet for anything you're building to last.