Applet: Neuron firing rate function with tangent plane
A fictitious representation of the firing rate $r(i,s)$ of a neuron in response to an input $i$ and nicotine level $s$. The graph of the function has a tangent plane at the location $(i,s)=(3,3)$ of the green point, so the function is differentiable there. By rotating the graph, you can see how the tangent plane touches the surface at the point $(3,3)$. There is no tangent plane to the graph at any point (such as the red point) along the fold of the graph; the function $r(i,s)$ is not differentiable at any point along the fold.
Applet file: neuronrate2Dtan.m
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This applet was created using LiveGraphics3D. To manipulate it, you can
- click and drag to rotate in any direction,
- shift + click and drag up/down to zoom out/in,
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