gobjects — Create an array of invalid graphics-handle placeholders.
gobjects creates arrays suitable for preallocating graphics handles. RunMat represents graphics handles as numeric values, so placeholders are stored as invalid numeric handle sentinels that can later be overwritten by real plotting handles.
Syntax
h = gobjects()
h = gobjects(sz...)Inputs
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
sz | SizeArg | Variadic | — | Output dimensions, either as separate scalar sizes or a size vector. |
Returns
| Name | Type | Description |
|---|---|---|
h | Any | Graphics-placeholder array; RunMat currently uses NaN numeric handle slots as its bounded representation. |
Errors
| Identifier | When | Message |
|---|---|---|
RunMat:gobjects:InvalidSize | A size is nonnumeric, nonintegral, logical, resident, or has invalid vector geometry. | gobjects: invalid size argument |
RunMat:gobjects:AllocationLimit | The requested shape exceeds addressable or allocatable placeholder storage. | gobjects: requested placeholder array is too large |
How gobjects works
gobjects()returns a 1-by-1 placeholder handle array.gobjects(n)returns an n-by-n placeholder handle array.gobjects(m,n,...)returns a placeholder handle array with the requested dimensions.gobjects([m n ...])accepts a numeric size vector.- Placeholder entries are not valid handles:
isgraphicsandishandlereturn false for them. - Assigned plotting handles retain normal numeric-handle fast paths and can be validated elementwise through
isgraphicsorishandle.
Does RunMat run gobjects on the GPU?
gobjects performs no provider dispatch and does not gather or upload GPU arrays.
GPU memory and residency
gobjects always returns host-side placeholder handles because graphics state is host-managed.
Examples
Preallocate an array and fill one graphics handle
h = gobjects(2,1);
h(1) = plot(1:3);
isgraphics(h)Expected output:
ans = [true; false]Use a size vector
h = gobjects([1 3]);
numel(h)Expected output:
ans = 3Using gobjects with coding agents
Open a RunMat example with live inputs, then ask the agent to explain how gobjects changes the result.
Run a small gobjects example, explain the result, then change one input and compare the output.
FAQ
Are gobjects placeholders valid graphics handles?⌄
No. They are invalid placeholders used for preallocation until a real graphics handle is assigned into the array.
Does gobjects create figures or axes?⌄
No. It only allocates placeholder handle values; plotting functions create the actual graphics objects.
Related Plotting functions
2D Charts
area · bar · errorbar · heatmap · hist · histogram · loglog · pie · plot · scatter · semilogx · semilogy · stairs · stem
Other
addpoints · ancestor · animatedline · axes · barh · caxis · cla · clf · clim · colorcube · colororder · copyobj · daspect · datacursormode · dataTipTextRow · fcontour · figure · fill · fill3 · findobj · fsurf · groot · hgload · hgsave · hidden · histogram2 · hold · line · linkaxes · openfig · opengl · pan · parula · patch · plotmatrix · plotyy · polarhistogram · polarplot · polarscatter · print · quiver3 · ribbon · saveas · savefig · sphere · stackedplot · subtitle · suptitle · text · textscatter · textscatter3 · triplot · waitbar · wordcloud · xlabel · xlim · xline · xscale · xtickangle · xtickformat · xticklabels · xticks · ylabel · ylim · yline · yscale · ytickangle · ytickformat · yticklabels · yticks · zlim · zoom
Open-source implementation
Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how gobjects is executed, line by line, in Rust.
- View the source for gobjects in Rust on GitHub
- Learn how the RunMat runtime works
- Found a bug? Open an issue with a minimal reproduction.
About RunMat
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