display — Display a value with a MATLAB-style variable-name header.
display(X) prints a MATLAB-style display block for X. When the callsite argument is a simple variable name, RunMat uses that name as the header. Expression and literal arguments use ans as the header. For classdef objects that define or inherit a registered display method, RunMat dispatches the object method first; otherwise it falls back to the generic formatter shared with disp.
Syntax
display(X)Inputs
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
X | Any | Yes | — | Value to display with a variable-name header. |
Returns
| Name | Type | Description |
|---|---|---|
ans | NumericArray | Empty matrix placeholder returned by sink invocation. |
Errors
| Identifier | When | Message |
|---|---|---|
RunMat:display:TooManyInputs | Too many input arguments are passed to display. | display: too many input arguments |
RunMat:display:GatherFailed | Input value cannot be gathered onto the host for rendering. | display: failed to gather value for display |
How display works
display(X)printsX = ...for simple variable arguments.display(expr)printsans = ...when the argument text is an expression, literal, or otherwise unavailable.- Single-line values are printed on the same line as the header.
- Multi-line values such as matrices, structs, tables, datetime arrays, duration arrays, and N-D pages are printed below the header.
- Objects and handle objects with a registered or inherited
displaymethod are dispatched through the class method surface before generic formatting. displayreturns an empty numeric matrix placeholder internally and suppresses automatic output.
Does RunMat run display on the GPU?
display performs no provider kernel dispatch and is excluded from fusion planning.
Gather behavior is inherited from the same runtime gather path used by disp.
GPU memory and residency
display is a sink. Provider-resident inputs are gathered to host memory for formatting and the returned placeholder is host-side.
Examples
Display a named variable
A = [1 2; 3 4];
display(A)Expected output:
A =
1 2
3 4Display an expression
display(1 + 2)Expected output:
ans = 3Display a string
msg = "ready";
display(msg)Expected output:
msg = readyUsing display with coding agents
Open a RunMat example with live inputs, then ask the agent to explain how display changes the result.
Run a small display example, explain the result, then change one input and compare the output.
FAQ
How is display different from disp?⌄
disp(X) prints only the value. display(X) prints a variable-name header such as X = before the value.
Does display support class-specific output?⌄
Yes for classes with a registered display method. The full matlab.mixin.CustomDisplay protocol is not yet modeled.
Does display gather GPU arrays?⌄
Yes. Like disp, display formats on the CPU and gathers provider-resident data through the active acceleration provider.
Related Io functions
Repl Fs
addpath · cd · copyfile · delete · dir · exist · fileattrib · fileparts · fullfile · genpath · getenv · getpref · isenv · isfile · isfolder · ispref · ls · matlabroot · memmapfile · mkdir · movefile · open · opentoline · path · pathsep · pcode · pwd · readstruct · rehash · restoredefaultpath · rmdir · rmpath · run · savepath · setenv · setpref · system · tempdir · tempname · uigetdir · uigetfile · uiputfile · unsetenv · userpath · what · winqueryreg · xmlread · xmlwrite
Tabular
arrayDatastore · csvread · csvwrite · detectImportOptions · dlmread · dlmwrite · fileDatastore · parquetDatastore · parquetinfo · parquetread · readcell · readmatrix · readtimetable · spreadsheetImportOptions · writecell · writematrix · writetable · writetimetable · xlsread · xlswrite
Filetext
fclose · feof · fgetl · fgets · fileread · filewrite · fopen · fprintf · fread · frewind · fwrite · readlines · writelines
Import
Json
Open-source implementation
Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how display is executed, line by line, in Rust.
- View the source for display in Rust on GitHub
- Learn how the RunMat runtime works
- Found a bug? Open an issue with a minimal reproduction.
About RunMat
RunMat is an open-source runtime that executes MATLAB-syntax code blazing on any GPU. It is licensed under the Apache 2.0 license.
- RunMat automatically optimizes your math for GPU execution on Apple, Nvidia, and AMD hardware. No code changes needed. Simulations that took hours now take minutes.
- Start running code in seconds. RunMat runs in the browser, on the desktop, or from the CLI. No license server, no IT ticket.