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$PlotResample

Status: Experimental

present and registered, but lightly documented and not yet covered by dedicated tests.

Description

$PlotResample[var, {f...}, {plotPoints, maxRecursion, maxPlotPoints, mesh, regionFunction, exclusions, colorFunction, colorFunctionScaling, filling, fillingStyle}]

Internal Plot metadata used by the renderer to re-sample curves at the current zoom. Not intended for direct use.

Examples (3)

Every input below was run against the current Mathilda build and its output recorded.

Applications (3)

A bare internal metadata symbol

In[1]:= Head[$PlotResample]
Out[1]= Symbol

HoldAll keeps the plotted bodies unevaluated

In[2]:= Attributes[$PlotResample]
Out[2]= {HoldAll, Protected}

No standalone meaning -- stays unevaluated

In[3]:= $PlotResample[x, {Sin[x]}, {}]
Out[3]= $PlotResample[x, {Sin[x]}, {}]

Implementation notes

Definition. $PlotResample is an internal metadata head that Plot embeds inside the Graphics object it returns, so the renderer can re-sample the curves when the view is zoomed. It is not a user function: graphics_init (src/graphics/graphics_init.c) stamps it HoldAll | Protected and sets a docstring that says outright it is not intended for direct use; the node is built by make_resample_meta in src/graphics/plot.c and consumed by the renderer in src/graphics/show.c.

Representation. $PlotResample is a bare EXPR_SYMBOL (Head[$PlotResample] is Symbol, Attributes[$PlotResample] is {HoldAll, Protected}). In use it heads a three-argument form $PlotResample[var, {bodies}, {opts...}], where bodies are the unevaluated plotted expressions and opts is the packed option vector (plotPoints, maxRecursion, maxPlotPoints, mesh, region function, exclusions, colour function and its scaling, filling, filling style). HoldAll is what keeps the bodies and the held option values unevaluated through the surrounding Graphics re-evaluation.

Usage & limits. It exists only as a carrier: show.c recognises the head while drawing and, on a zoom, re-samples the stored bodies over the new coordinate window instead of rescaling a fixed polyline. It has no standalone value — written by hand it simply stays unevaluated — and is an implementation detail of Plot's zoomable output.

Attributes: HoldAll, Protected.

References

Notes & additional examples

Notes

$PlotResample is internal Plot metadata, not a user-facing function. Plot embeds a $PlotResample[var, {bodies}, {opts...}] node inside the Graphics object it returns so the renderer can re-sample the curves when the view is zoomed, rather than rescaling a fixed polyline.

Its HoldAll attribute keeps the plotted bodies and held option values unevaluated through the surrounding Graphics re-evaluation. It carries no standalone value — written by hand it simply stays unevaluated, as above — and should be treated as an implementation detail of Plot's zoomable output.