persistent()
Programming
persistent() is a MATLAB®-compatible programming function for declare variables that retain their values between calls to the same function. initialise to `[]` on first declaration; check with `isempty()`. Run it online in your browser with SimLab — free, no install, no license required.
Declare variables that retain their values between calls to the same function. Initialise to `[]` on first declaration; check with `isempty()`.
Syntax
persistent x
persistent x y z
Examples — run persistent() in your browser
function n = counter() persistent count if isempty(count); count = 0; end count = count + 1; n = count; end▶ Run
See Also
Frequently Asked Questions about persistent()
Is the persistent() function free to use in SimLab?
The browser workspace requires no MATLAB® license or installation. Connected features require network access and may have account, tier, availability, or usage limits. You can open persistent() and 510+ other MATLAB®-compatible function references at simulations4all.com/simlab.
Do I need to install MATLAB to use persistent()?
No. SimLab’s core parser, workspace state, and most functions run locally in your browser. The persistent() function requires no MATLAB® license or desktop software download.
What does persistent() do?
Declare variables that retain their values between calls to the same function. Initialise to `[]` on first declaration; check with `isempty()`. It is a MATLAB®-compatible programming function available in SimLab with the same calling syntax as MATLAB® — typically: persistent x.
Can I run persistent() in my browser?
Yes. Open SimLab at simulations4all.com/simlab, write or paste code that calls persistent(), and run it. This function’s calculation runs locally in the browser. SimLab session analytics, sharing, feedback, and eligible acceleration have separate network boundaries.
Try SimLab — MATLAB®-compatible, free, in your browser
510+ functions. Runs in your browser. No install. No license.
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