Files
Meshtastic-Android/main/en/developer/measurement.html
T

52 lines
49 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
<!DOCTYPE html> <html lang="en-US"> <head> <meta charset="UTF-8"> <meta http-equiv="X-UA-Compatible" content="IE=Edge"> <link rel="stylesheet" href="/Meshtastic-Android/main/assets/css/just-the-docs-default.css"> <link rel="stylesheet" href="/Meshtastic-Android/main/assets/css/just-the-docs-head-nav.css" id="jtd-head-nav-stylesheet"> <style id="jtd-nav-activation"> .site-nav > ul.nav-list:first-child > li > a, .site-nav > ul.nav-list:first-child > li > ul > li:not(:nth-child(9)) > a, .site-nav > ul.nav-list:first-child > li > ul > li > ul > li a { background-image: none; } .site-nav > ul.nav-list:not(:first-child) a, .site-nav li.external a { background-image: none; } .site-nav > ul.nav-list:first-child > li:nth-child(4) > ul > li:nth-child(9) > a { font-weight: 600; text-decoration: none; }.site-nav > ul.nav-list:first-child > li:nth-child(4) > button svg, .site-nav > ul.nav-list:first-child > li:nth-child(4) > ul > li:nth-child(9) > button svg { transform: rotate(-90deg); }.site-nav > ul.nav-list:first-child > li.nav-list-item:nth-child(4) > ul.nav-list, .site-nav > ul.nav-list:first-child > li.nav-list-item:nth-child(4) > ul.nav-list > li.nav-list-item:nth-child(9) > ul.nav-list { display: block; } </style> <script src="/Meshtastic-Android/main/assets/js/vendor/lunr.min.js"></script> <script src="/Meshtastic-Android/main/assets/js/just-the-docs.js"></script> <meta name="viewport" content="width=device-width, initial-scale=1"> <!-- Begin Jekyll SEO tag v2.9.0 --> <title>Measurement &amp; Formatting | Meshtastic Android</title> <meta name="generator" content="Jekyll v4.4.1" /> <meta property="og:title" content="Measurement &amp; Formatting" /> <meta property="og:locale" content="en_US" /> <meta name="description" content="How MetricFormatter and NumberFormatter format measurements, and how the app resolves metric or imperial units from locale and user preference." /> <meta name="twitter:description" property="og:description" content="How MetricFormatter and NumberFormatter format measurements, and how the app resolves metric or imperial units from locale and user preference." /> <link rel="canonical" href="/Meshtastic-Android/main/en/developer/measurement.html" /> <meta property="og:url" content="/Meshtastic-Android/main/en/developer/measurement.html" /> <meta property="og:site_name" content="Meshtastic Android" /> <meta property="og:type" content="website" /> <meta name="twitter:card" content="summary" /> <meta name="twitter:title" content="Measurement &amp; Formatting" /> <script type="application/ld+json"> {"@context":"https://schema.org","@type":"WebPage","description":"How MetricFormatter and NumberFormatter format measurements, and how the app resolves metric or imperial units from locale and user preference.","headline":"Measurement &amp; Formatting","url":"/Meshtastic-Android/main/en/developer/measurement.html"}</script> <!-- End Jekyll SEO tag --> <!-- Inter font from Google Fonts --> <link rel="preconnect" href="https://fonts.googleapis.com"> <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin> <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap" rel="stylesheet"> <style> /* M3-inspired typography */ :root { --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif; --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', ui-monospace, monospace; } body, .site-title, .search-input { font-family: var(--font-sans) !important; } code, pre, .highlight { font-family: var(--font-mono) !important; font-size: 0.875em; } /* M3 surface elevation & rounding */ .main-content table { border-radius: 12px; overflow: hidden; } .main-content blockquote { border-radius: 12px; padding: 1rem 1.25rem; border-left-width: 4px; } .main-content pre { border-radius: 12px; } .main-content code { border-radius: 6px; padding: 0.15em 0.4em; } /* Smooth transitions for theme switching */ body, .side-bar, .main, .main-content, .site-header, .search-input, .search-results, a { transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease; } /* Theme toggle button styling */ .theme-toggle { background: none; border: 1px solid var(--border-color, #D5D6E0); border-radius: 20px; padding: 6px 12px; cursor: pointer; font-family: var(--font-sans); font-size: 0.75rem; font-weight: 500; display: inline-flex; align-items: center; gap: 6px; color: inherit; margin: 0 auto; transition: background-color 0.2s ease, border-color 0.2s ease; } .theme-toggle:hover { background-color: rgba(128, 128, 128, 0.1); } .theme-toggle-wrap { text-align: center; padding: 12px 0 4px; } /* Heading weight refinement */ h1, h2, h3, h4, h5, h6 { font-weight: 600; letter-spacing: -0.01em; } h1 { font-weight: 700; letter-spacing: -0.02em; } /* Smooth anchor scroll */ html { scroll-behavior: smooth; } /* Language switcher */ .language-switcher { display: inline-block; position: relative; margin-left: 8px; } .language-switcher-btn { cursor: pointer; font-size: 0.8rem; font-weight: 500; font-family: var(--font-sans); list-style: none; padding: 4px 10px; border: 1px solid var(--border-color, #D5D6E0); border-radius: 16px; display: inline-flex; align-items: center; gap: 4px; transition: background-color 0.2s ease; } .language-switcher-btn:hover { background-color: rgba(128, 128, 128, 0.1); } .language-switcher[open] .language-switcher-list { display: block; } .language-switcher-list { position: absolute; top: 100%; right: 0; left: auto; z-index: 100; list-style: none; padding: 8px 0; margin: 4px 0 0; min-width: 140px; background: var(--body-background-color, #fff); border: 1px solid var(--border-color, #D5D6E0); border-radius: 12px; box-shadow: 0 4px 12px rgba(0,0,0,0.1); } .language-switcher-list li { padding: 0; } .language-switcher-list a { display: block; padding: 6px 16px; text-decoration: none; font-size: 0.85rem; color: inherit; } .language-switcher-list a:hover { background-color: rgba(103, 234, 148, 0.15); } /* Version switcher (shares the language-switcher dropdown styling) */ .version-switcher { margin-left: 8px; } .version-switcher[hidden] { display: none; } /* Link out to the upstream meshtastic.org docs */ .upstream-docs-link { display: inline-flex; align-items: center; margin-left: 8px; padding: 4px 10px; border: 1px solid var(--border-color, #D5D6E0); border-radius: 16px; font-size: 0.8rem; font-weight: 500; font-family: var(--font-sans); text-decoration: none; color: inherit; transition: background-color 0.2s ease; } .upstream-docs-link:hover { background-color: rgba(128, 128, 128, 0.1); } </style> <script> // Respect OS preference on first visit, then remember user choice (function() { var stored = localStorage.getItem('jtd-theme'); if (stored) return; // will be applied by jtd.setTheme below if (window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches) { localStorage.setItem('jtd-theme', 'meshtastic-dark'); } })(); </script> </head> <body> <a class="skip-to-main" href="#main-content">Skip to main content</a> <svg xmlns="http://www.w3.org/2000/svg" class="d-none"> <symbol id="svg-link" viewBox="0 0 24 24"> <title>Link</title> <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-link"> <path d="M10 13a5 5 0 0 0 7.54.54l3-3a5 5 0 0 0-7.07-7.07l-1.72 1.71"></path><path d="M14 11a5 5 0 0 0-7.54-.54l-3 3a5 5 0 0 0 7.07 7.07l1.71-1.71"></path> </svg> </symbol> <symbol id="svg-menu" viewBox="0 0 24 24"> <title>Menu</title> <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-menu"> <line x1="3" y1="12" x2="21" y2="12"></line><line x1="3" y1="6" x2="21" y2="6"></line><line x1="3" y1="18" x2="21" y2="18"></line> </svg> </symbol> <symbol id="svg-arrow-right" viewBox="0 0 24 24"> <title>Expand</title> <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-chevron-right"> <polyline points="9 18 15 12 9 6"></polyline> </svg> </symbol> <!-- Feather. MIT License: https://github.com/feathericons/feather/blob/master/LICENSE --> <symbol id="svg-external-link" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-external-link"> <title id="svg-external-link-title">(external link)</title> <path d="M18 13v6a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2V8a2 2 0 0 1 2-2h6"></path><polyline points="15 3 21 3 21 9"></polyline><line x1="10" y1="14" x2="21" y2="3"></line> </symbol> <symbol id="svg-doc" viewBox="0 0 24 24"> <title>Document</title> <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-file"> <path d="M13 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V9z"></path><polyline points="13 2 13 9 20 9"></polyline> </svg> </symbol> <symbol id="svg-search" viewBox="0 0 24 24"> <title>Search</title> <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-search"> <circle cx="11" cy="11" r="8"></circle><line x1="21" y1="21" x2="16.65" y2="16.65"></line> </svg> </symbol> <!-- Bootstrap Icons. MIT License: https://github.com/twbs/icons/blob/main/LICENSE.md --> <symbol id="svg-copy" viewBox="0 0 16 16"> <title>Copy</title> <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-clipboard" viewBox="0 0 16 16"> <path d="M4 1.5H3a2 2 0 0 0-2 2V14a2 2 0 0 0 2 2h10a2 2 0 0 0 2-2V3.5a2 2 0 0 0-2-2h-1v1h1a1 1 0 0 1 1 1V14a1 1 0 0 1-1 1H3a1 1 0 0 1-1-1V3.5a1 1 0 0 1 1-1h1v-1z"/> <path d="M9.5 1a.5.5 0 0 1 .5.5v1a.5.5 0 0 1-.5.5h-3a.5.5 0 0 1-.5-.5v-1a.5.5 0 0 1 .5-.5h3zm-3-1A1.5 1.5 0 0 0 5 1.5v1A1.5 1.5 0 0 0 6.5 4h3A1.5 1.5 0 0 0 11 2.5v-1A1.5 1.5 0 0 0 9.5 0h-3z"/> </svg> </symbol> <symbol id="svg-copied" viewBox="0 0 16 16"> <title>Copied</title> <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-clipboard-check-fill" viewBox="0 0 16 16"> <path d="M6.5 0A1.5 1.5 0 0 0 5 1.5v1A1.5 1.5 0 0 0 6.5 4h3A1.5 1.5 0 0 0 11 2.5v-1A1.5 1.5 0 0 0 9.5 0h-3Zm3 1a.5.5 0 0 1 .5.5v1a.5.5 0 0 1-.5.5h-3a.5.5 0 0 1-.5-.5v-1a.5.5 0 0 1 .5-.5h3Z"/> <path d="M4 1.5H3a2 2 0 0 0-2 2V14a2 2 0 0 0 2 2h10a2 2 0 0 0 2-2V3.5a2 2 0 0 0-2-2h-1v1A2.5 2.5 0 0 1 9.5 5h-3A2.5 2.5 0 0 1 4 2.5v-1Zm6.854 7.354-3 3a.5.5 0 0 1-.708 0l-1.5-1.5a.5.5 0 0 1 .708-.708L7.5 10.793l2.646-2.647a.5.5 0 0 1 .708.708Z"/> </svg> </symbol> </svg> <header class="side-bar"> <div class="site-header"> <a href="/Meshtastic-Android/main/" class="site-title lh-tight"> Meshtastic Android </a> <button id="menu-button" class="site-button btn-reset" aria-label="Menu" aria-expanded="false"> <svg viewBox="0 0 24 24" class="icon" aria-hidden="true"><use xlink:href="#svg-menu"></use></svg> </button> </div> <nav aria-label="Main" id="site-nav" class="site-nav"> <ul class="nav-list"><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/" class="nav-list-link">Home</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/" class="nav-list-link">Home</a></li><li class="nav-list-item"><button class="nav-list-expander btn-reset" aria-label="User Guide submenu" aria-expanded="false"> <svg viewBox="0 0 24 24" aria-hidden="true"><use xlink:href="#svg-arrow-right"></use></svg> </button><a href="/Meshtastic-Android/main/en/user.html" class="nav-list-link">User Guide</a><ul class="nav-list"><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/onboarding.html" class="nav-list-link">Getting Started</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/onboarding.html" class="nav-list-link">Getting Started</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/connections.html" class="nav-list-link">Connexions</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/connections.html" class="nav-list-link">Connections</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/messages-and-channels.html" class="nav-list-link">Messages & Channels</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/messages-and-channels.html" class="nav-list-link">Messages & Channels</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/nodes.html" class="nav-list-link">Nœuds</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/nodes.html" class="nav-list-link">Nodes</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/node-metrics.html" class="nav-list-link">Node Metrics</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/node-metrics.html" class="nav-list-link">Node Metrics</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/map-and-waypoints.html" class="nav-list-link">Map & Waypoints</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/map-and-waypoints.html" class="nav-list-link">Map & Waypoints</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/settings-radio-user.html" class="nav-list-link">Settings — Radio & User</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/settings-radio-user.html" class="nav-list-link">Settings — Radio & User</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/settings-module-admin.html" class="nav-list-link">Settings — Modules & Admin</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/settings-module-admin.html" class="nav-list-link">Settings — Modules & Admin</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/tak.html" class="nav-list-link">TAK Integration</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/tak.html" class="nav-list-link">TAK Integration</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/mqtt.html" class="nav-list-link">MQTT</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/mqtt.html" class="nav-list-link">MQTT</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/discovery.html" class="nav-list-link">Découverte de maille locale</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/discovery.html" class="nav-list-link">Local Mesh Discovery</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/firmware.html" class="nav-list-link">Firmware Updates</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/firmware.html" class="nav-list-link">Firmware Updates</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/desktop.html" class="nav-list-link">Desktop App</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/desktop.html" class="nav-list-link">Desktop App</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/signal-meter.html" class="nav-list-link">How the Meshtastic Signal Meter Works</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/signal-meter.html" class="nav-list-link">How the Meshtastic Signal Meter Works</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/units-and-locale.html" class="nav-list-link">Units, Measurement & Locale</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/units-and-locale.html" class="nav-list-link">Units, Measurement & Locale</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/fr-rCA/user/translate.html" class="nav-list-link">Translate the App</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/translate.html" class="nav-list-link">Translate the App</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/app-functions.html" class="nav-list-link">App Functions</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/widget.html" class="nav-list-link">Home Screen Widget</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/help-and-docs.html" class="nav-list-link">Help & In-App Docs</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/user/debug-logs.html" class="nav-list-link">Debug Logs</a></li></ul></li><li class="nav-list-item"><button class="nav-list-expander btn-reset" aria-label="Developer Guide submenu" aria-expanded="false"> <svg viewBox="0 0 24 24" aria-hidden="true"><use xlink:href="#svg-arrow-right"></use></svg> </button><a href="/Meshtastic-Android/main/en/developer.html" class="nav-list-link">Developer Guide</a><ul class="nav-list"><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/architecture.html" class="nav-list-link">Architecture</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/codebase.html" class="nav-list-link">Codebase</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/adding-a-feature-module.html" class="nav-list-link">Adding a Feature Module</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/navigation-and-deep-links.html" class="nav-list-link">Navigation & Deep Links</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/transport.html" class="nav-list-link">Transport</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/persistence.html" class="nav-list-link">Persistence</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/testing.html" class="nav-list-link">Testing</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/contributing.html" class="nav-list-link">Contributing</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/measurement.html" class="nav-list-link">Measurement & Formatting</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/test-builds.html" class="nav-list-link">Test Builds & Obtainium</a></li><li class="nav-list-item"><a href="/Meshtastic-Android/main/en/developer/documentation-style.html" class="nav-list-link">Documentation Style</a></li></ul></li></ul> </nav> <div class="d-md-block d-sm-none"> <div class="site-footer"> This site uses <a href="https://github.com/just-the-docs/just-the-docs">Just the Docs</a>, a documentation theme for Jekyll. </div> </div> </header> <div class="main" id="top"> <div id="main-header" class="main-header"> <div class="search" role="search"> <div class="search-input-wrap"> <input type="text" id="search-input" class="search-input" tabindex="0" placeholder="Search Meshtastic Android" autocomplete="off"> <label for="search-input" class="search-label"> <span class="sr-only">Search Meshtastic Android</span> <svg viewBox="0 0 24 24" class="search-icon" aria-hidden="true"><use xlink:href="#svg-search"></use></svg> </label> </div> <div id="search-results" class="search-results"></div> </div> <div class="theme-toggle-wrap"> <button class="theme-toggle" id="theme-toggle" aria-label="Toggle dark mode" title="Toggle light/dark theme" onclick="toggleMeshtasticTheme()"> <span id="theme-icon">🌙</span> <span id="theme-label">Dark</span> </button> <details class="language-switcher version-switcher" id="version-switcher" aria-label="Documentation version" hidden> <summary class="language-switcher-btn" title="Switch documentation version"> 🏷️ <span id="version-current"></span> </summary> <ul class="language-switcher-list" id="version-switcher-list"></ul> </details> <script> (function() { var baseurl = '/Meshtastic-Android/main'; var root = baseurl; var channel = 'latest'; // /main/, /vX.Y.Z/ or a prerelease snapshot like /v2.8.0-open.1/. var match = baseurl.match(/^(.*)\/(main|v\d+\.\d+\.\d+(?:-(?:open|closed)\.\d+)?)$/); if (match) { root = match[1]; channel = match[2]; } fetch(root + '/versions.json') .then(function(res) { return res.ok ? res.json() : Promise.reject(); }) .then(function(data) { var switcher = document.getElementById('version-switcher'); var list = document.getElementById('version-switcher-list'); var current = document.getElementById('version-current'); if (!switcher || !list || !current) return; // Keep the reader on the same page when switching channels; a page // that doesn't exist in the target version lands on the 404 page. var relativePath = location.pathname.slice(baseurl.length) + location.hash; var entries = []; if (data.latest) { entries.push({ id: 'latest', label: 'latest (v' + data.latest + ')', base: root }); } // Prereleases are documented ahead of general availability, so the track // is always spelled out — a reader must not mistake a closed-testing // snapshot for a shipped release. (data.prereleases || []).forEach(function(p) { entries.push({ id: p.dir, label: p.dir.replace(/^v/, 'v') + ' — ' + p.track + ' testing', base: root + '/' + p.dir }); }); if (data.hasMain) { entries.push({ id: 'main', label: 'main (unreleased snapshot)', base: root + '/main' }); } (data.versions || []).forEach(function(v) { entries.push({ id: 'v' + v, label: 'v' + v, base: root + '/v' + v }); }); var currentEntry = entries.filter(function(e) { return e.id === channel; })[0]; current.textContent = currentEntry ? currentEntry.label : channel; var others = entries.filter(function(e) { return e.id !== channel; }); if (others.length === 0) return; others.forEach(function(e) { var li = document.createElement('li'); var a = document.createElement('a'); a.href = e.base + relativePath; a.textContent = e.label; li.appendChild(a); list.appendChild(li); }); switcher.hidden = false; }) .catch(function() { /* no manifest (local build) — leave switcher hidden */ }); })(); </script> <a class="upstream-docs-link" href="https://meshtastic.org/docs/" title="Official Meshtastic documentation (meshtastic.org)">Meshtastic Docs ↗</a> </div> <script> function toggleMeshtasticTheme() { var current = localStorage.getItem('jtd-theme') || 'meshtastic'; var next = (current === 'meshtastic-dark') ? 'meshtastic' : 'meshtastic-dark'; if (typeof jtd !== 'undefined' && typeof jtd.setTheme === 'function') { jtd.setTheme(next); } localStorage.setItem('jtd-theme', next); var icon = document.getElementById('theme-icon'); var label = document.getElementById('theme-label'); if (icon && label) { icon.textContent = (next === 'meshtastic-dark') ? '☀️' : '🌙'; label.textContent = (next === 'meshtastic-dark') ? 'Light' : 'Dark'; } } // Apply stored/OS theme on page load (function() { var theme = localStorage.getItem('jtd-theme') || 'meshtastic'; // Sync toggle label immediately var icon = document.getElementById('theme-icon'); var label = document.getElementById('theme-label'); if (icon && label) { icon.textContent = (theme === 'meshtastic-dark') ? '☀️' : '🌙'; label.textContent = (theme === 'meshtastic-dark') ? 'Light' : 'Dark'; } // Apply theme once jtd is ready function tryApply() { if (typeof jtd !== 'undefined' && typeof jtd.setTheme === 'function') { jtd.setTheme(theme); } else { setTimeout(tryApply, 50); } } tryApply(); })(); </script> </div> <div class="main-content-wrap"> <nav aria-label="Breadcrumb" class="breadcrumb-nav"> <ol class="breadcrumb-nav-list"> <li class="breadcrumb-nav-list-item"><a href="/Meshtastic-Android/main/en/developer.html">Developer Guide</a></li> <li class="breadcrumb-nav-list-item"><span>Measurement & Formatting</span></li> </ol> </nav> <div id="main-content" class="main-content"> <main> <h1 id="measurement--formatting"> <a href="#measurement--formatting" class="anchor-heading" aria-labelledby="measurement--formatting"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Measurement &amp; Formatting </h1> <p>How the Meshtastic Android/KMP app formats numbers, units, and locale-sensitive values.</p> <h2 id="overview"> <a href="#overview" class="anchor-heading" aria-labelledby="overview"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Overview </h2> <p>All measurement data transmitted by Meshtastic nodes uses <strong>metric units</strong> (meters, °C, hPa, m/s, etc.). The app converts and formats these values for display using two core utilities:</p> <div class="table-wrapper"><table> <thead> <tr> <th>Utility</th> <th>Location</th> <th>Purpose</th> </tr> </thead> <tbody> <tr> <td><code class="language-plaintext highlighter-rouge">MetricFormatter</code></td> <td><code class="language-plaintext highlighter-rouge">core/common/.../util/MetricFormatter.kt</code></td> <td>Converts and formats physical measurements (temperature, pressure, speed, etc.)</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">NumberFormatter</code></td> <td><code class="language-plaintext highlighter-rouge">core/common/.../util/NumberFormatter.kt</code></td> <td>Decimal formatting: <code class="language-plaintext highlighter-rouge">format</code> follows the OS locale, <code class="language-plaintext highlighter-rouge">formatInvariant</code> keeps a fixed dot separator</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">MeasureFormatting</code></td> <td><code class="language-plaintext highlighter-rouge">core/common/.../util/MeasureFormatting.kt</code></td> <td>Pairs a fixed English unit symbol with a locale-formatted number, for the units that convert</td> </tr> </tbody> </table></div> <p>Both live in <code class="language-plaintext highlighter-rouge">org.meshtastic.core.common.util</code> and are available to all KMP targets (Android, Desktop, iOS).</p> <h2 id="metricformatter-api"> <a href="#metricformatter-api" class="anchor-heading" aria-labelledby="metricformatter-api"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> MetricFormatter API </h2> <p><code class="language-plaintext highlighter-rouge">MetricFormatter</code> is a Kotlin <code class="language-plaintext highlighter-rouge">object</code> with pure functions for each measurement type:</p> <div class="language-kotlin highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="kd">object</span> <span class="nc">MetricFormatter</span> <span class="p">{</span>
<span class="k">fun</span> <span class="nf">temperature</span><span class="p">(</span><span class="n">celsius</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">isFahrenheit</span><span class="p">:</span> <span class="nc">Boolean</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">voltage</span><span class="p">(</span><span class="n">volts</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span> <span class="p">=</span> <span class="mi">2</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">current</span><span class="p">(</span><span class="n">milliAmps</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span> <span class="p">=</span> <span class="mi">1</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">percent</span><span class="p">(</span><span class="n">value</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span> <span class="p">=</span> <span class="mi">1</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">humidity</span><span class="p">(</span><span class="n">value</span><span class="p">:</span> <span class="nc">Float</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">pressure</span><span class="p">(</span><span class="n">hPa</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span> <span class="p">=</span> <span class="mi">1</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">snr</span><span class="p">(</span><span class="n">value</span><span class="p">:</span> <span class="nc">Float</span><span class="p">?,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span> <span class="p">=</span> <span class="mi">1</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">rssi</span><span class="p">(</span><span class="n">value</span><span class="p">:</span> <span class="nc">Int</span><span class="p">?):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">degreeSymbol</span><span class="p">(</span><span class="n">isFahrenheit</span><span class="p">:</span> <span class="nc">Boolean</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">percent</span><span class="p">(</span><span class="n">value</span><span class="p">:</span> <span class="nc">Int</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">windSpeed</span><span class="p">(</span><span class="n">metersPerSecond</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">isImperial</span><span class="p">:</span> <span class="nc">Boolean</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span> <span class="p">=</span> <span class="mi">1</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">rainfall</span><span class="p">(</span><span class="n">millimeters</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">isImperial</span><span class="p">:</span> <span class="nc">Boolean</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span> <span class="p">=</span> <span class="mi">1</span><span class="p">):</span> <span class="nc">String</span>
<span class="k">fun</span> <span class="nf">weight</span><span class="p">(</span><span class="n">kilograms</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">isImperial</span><span class="p">:</span> <span class="nc">Boolean</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span> <span class="p">=</span> <span class="mi">2</span><span class="p">):</span> <span class="nc">String</span>
<span class="p">}</span>
<span class="n">`snr`</span> <span class="n">and</span> <span class="n">`rssi`</span> <span class="n">take</span> <span class="n">a</span> <span class="n">nullable</span> <span class="n">reading</span> <span class="n">and</span> <span class="n">render</span> <span class="n">the</span> <span class="err">`—`</span> <span class="n">placeholder</span> <span class="k">when</span> <span class="n">it</span> <span class="k">is</span> <span class="n">absent</span><span class="p">.</span>
</code></pre></div></div> <h3 id="usage"> <a href="#usage" class="anchor-heading" aria-labelledby="usage"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Usage </h3> <div class="language-kotlin highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c1">// Temperature — Fahrenheit conversion is handled automatically</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">temperature</span><span class="p">(</span><span class="mf">22.5f</span><span class="p">,</span> <span class="n">isFahrenheit</span> <span class="p">=</span> <span class="k">true</span><span class="p">)</span> <span class="c1">// "72.5°F"</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">temperature</span><span class="p">(</span><span class="mf">22.5f</span><span class="p">,</span> <span class="n">isFahrenheit</span> <span class="p">=</span> <span class="k">false</span><span class="p">)</span> <span class="c1">// "22.5°C"</span>
<span class="c1">// Signal metrics</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">snr</span><span class="p">(-</span><span class="mf">5.2f</span><span class="p">)</span> <span class="c1">// "-5.2 dB"</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">rssi</span><span class="p">(-</span><span class="mi">97</span><span class="p">)</span> <span class="c1">// "-97 dBm"</span>
<span class="c1">// Environment</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">pressure</span><span class="p">(</span><span class="mf">1013.25f</span><span class="p">)</span> <span class="c1">// "1013.3 hPa"</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">humidity</span><span class="p">(</span><span class="mf">65.0f</span><span class="p">)</span> <span class="c1">// "65%"</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">windSpeed</span><span class="p">(</span><span class="mf">3.7f</span><span class="p">,</span> <span class="n">isImperial</span> <span class="p">=</span> <span class="k">false</span><span class="p">)</span> <span class="c1">// "13.3 km/h"</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">windSpeed</span><span class="p">(</span><span class="mf">3.7f</span><span class="p">,</span> <span class="n">isImperial</span> <span class="p">=</span> <span class="k">true</span><span class="p">)</span> <span class="c1">// "8.3 mph"</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">rainfall</span><span class="p">(</span><span class="mf">12.3f</span><span class="p">,</span> <span class="n">isImperial</span> <span class="p">=</span> <span class="k">false</span><span class="p">)</span> <span class="c1">// "12.3 mm"</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">rainfall</span><span class="p">(</span><span class="mf">12.3f</span><span class="p">,</span> <span class="n">isImperial</span> <span class="p">=</span> <span class="k">true</span><span class="p">)</span> <span class="c1">// "0.5 in"</span>
<span class="c1">// Power</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">voltage</span><span class="p">(</span><span class="mf">3.95f</span><span class="p">)</span> <span class="c1">// "3.95 V"</span>
<span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">current</span><span class="p">(</span><span class="mf">125.0f</span><span class="p">)</span> <span class="c1">// "125.0 mA"</span>
</code></pre></div></div> <h2 id="numberformatter"> <a href="#numberformatter" class="anchor-heading" aria-labelledby="numberformatter"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> NumberFormatter </h2> <p><code class="language-plaintext highlighter-rouge">NumberFormatter</code> has two halves, and picking the wrong one is the mistake to avoid:</p> <div class="language-kotlin highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="kd">object</span> <span class="nc">NumberFormatter</span> <span class="p">{</span>
<span class="k">fun</span> <span class="nf">format</span><span class="p">(</span><span class="n">value</span><span class="p">:</span> <span class="nc">Double</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span><span class="p">):</span> <span class="nc">String</span> <span class="c1">// follows the OS locale</span>
<span class="k">fun</span> <span class="nf">format</span><span class="p">(</span><span class="n">value</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span><span class="p">):</span> <span class="nc">String</span> <span class="c1">// follows the OS locale</span>
<span class="k">fun</span> <span class="nf">formatInvariant</span><span class="p">(</span><span class="n">value</span><span class="p">:</span> <span class="nc">Double</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span><span class="p">):</span> <span class="nc">String</span> <span class="c1">// fixed dot separator</span>
<span class="p">}</span>
</code></pre></div></div> <p><strong>Use 0 for anything a person reads.</strong> It delegates to the platform’s own number formatter through an <code class="language-plaintext highlighter-rouge">expect</code>/<code class="language-plaintext highlighter-rouge">actual</code> (<code class="language-plaintext highlighter-rouge">java.text.NumberFormat</code> on JVM and Android), so a number reads the way that user writes numbers. <code class="language-plaintext highlighter-rouge">NaN</code> and infinity render as <code class="language-plaintext highlighter-rouge">—</code>.</p> <p><strong>Use 0 for anything a machine parses</strong> — a CoT payload another client reads, or a value written out and read back. Localizing those turns <code class="language-plaintext highlighter-rouge">1.5</code> into <code class="language-plaintext highlighter-rouge">1,5</code> and breaks the reader. It rounds half away from zero to match the locale path, which matters because firmware reports SNR in quarter-dB steps and ties are routine.</p> <h2 id="unit-conversion"> <a href="#unit-conversion" class="anchor-heading" aria-labelledby="unit-conversion"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Unit conversion </h2> <p>Four measurements convert away from metric for display, each gated by a boolean flag sourced from the device locale or preferences:</p> <div class="table-wrapper"><table> <thead> <tr> <th>Measurement</th> <th>Flag</th> <th>Source</th> <th>Conversion</th> </tr> </thead> <tbody> <tr> <td><code class="language-plaintext highlighter-rouge">temperature</code></td> <td><code class="language-plaintext highlighter-rouge">isFahrenheit</code></td> <td><code class="language-plaintext highlighter-rouge">getSystemTemperatureUnit()</code></td> <td><code class="language-plaintext highlighter-rouge">°F = °C × 1.8 + 32</code></td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">windSpeed</code></td> <td><code class="language-plaintext highlighter-rouge">isImperial</code></td> <td><code class="language-plaintext highlighter-rouge">getSystemMeasurementSystem()</code></td> <td>m/s × 3.6 → km/h, or × 2.23694 → mph</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">rainfall</code></td> <td><code class="language-plaintext highlighter-rouge">isImperial</code></td> <td><code class="language-plaintext highlighter-rouge">getSystemMeasurementSystem()</code></td> <td>mm ÷ 25.4 → in</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">weight</code></td> <td><code class="language-plaintext highlighter-rouge">isImperial</code></td> <td><code class="language-plaintext highlighter-rouge">getSystemMeasurementSystem()</code></td> <td>kg × 2.20462 → lb</td> </tr> </tbody> </table></div> <p>The two source functions (in <code class="language-plaintext highlighter-rouge">core/common/.../util/MeasurementSystem.kt</code>) are deliberately separate: some locales mix systems (the UK uses miles for distance but Celsius for temperature), so temperature must never be derived from the distance unit. On Android, <code class="language-plaintext highlighter-rouge">getSystemTemperatureUnit()</code> delegates to <code class="language-plaintext highlighter-rouge">androidx.core.text.util.LocalePreferences</code>, which resolves CLDR locale data and honors the Android 14+ Regional preferences temperature override.</p> <p>The in-app <strong>Units</strong> choice (<code class="language-plaintext highlighter-rouge">UnitsOverride</code>, stored in <code class="language-plaintext highlighter-rouge">UiPrefs</code>) is folded in by <code class="language-plaintext highlighter-rouge">LocaleUnitsProvider</code>, which is the only place display code takes units from. A Konsist rule (<code class="language-plaintext highlighter-rouge">MeasurementSystemSourceTest</code>) keeps direct reads of the OS resolution out of the rest of the codebase, because a direct read follows the locale but ignores the setting. A forced system carries its temperature with it (metric → °C, imperial → °F), overriding even an explicit OS regional temperature preference.</p> <p><code class="language-plaintext highlighter-rouge">getSystemMeasurementSystem()</code> resolves the locale in this order (temperature is separate: as described above, <code class="language-plaintext highlighter-rouge">getSystemTemperatureUnit()</code> reads the regional temperature preference via <code class="language-plaintext highlighter-rouge">LocalePreferences</code>, shares only the region backfill, and falls back to Celsius):</p> <ol> <li>The <code class="language-plaintext highlighter-rouge">ms</code> Unicode extension (the Android 16+ Measurement system preference) wins outright.</li> <li>A locale with no region — the in-app language picker offers bare tags like <code class="language-plaintext highlighter-rouge">en</code> — takes its region from the system configuration rather than letting ICU guess one from the language.</li> <li>Anything still unclassified falls back to metric, never imperial.</li> </ol> <p>The Android and Desktop implementations share the region table and the override reader in <code class="language-plaintext highlighter-rouge">commonMain</code>, so the two clients can’t disagree about the same locale.</p> <p>Everything else (voltage, current, pressure, SNR, RSSI, humidity, percent) displays in its native metric units. The user-facing <a href="../user/units-and-locale">Units &amp; Locale</a> page explains what end users see.</p> <h2 id="adding-a-new-measurement-type"> <a href="#adding-a-new-measurement-type" class="anchor-heading" aria-labelledby="adding-a-new-measurement-type"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Adding a new measurement type </h2> <p>To add a new measurement formatter:</p> <ol> <li> <p><strong>Add a function to 0</strong> in <code class="language-plaintext highlighter-rouge">core/common/src/commonMain/kotlin/org/meshtastic/core/common/util/MetricFormatter.kt</code>:</p> <div class="language-kotlin highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">fun</span> <span class="nf">radiation</span><span class="p">(</span><span class="n">microSieverts</span><span class="p">:</span> <span class="nc">Float</span><span class="p">,</span> <span class="n">decimalPlaces</span><span class="p">:</span> <span class="nc">Int</span> <span class="p">=</span> <span class="mi">2</span><span class="p">):</span> <span class="nc">String</span> <span class="p">=</span>
<span class="s">"${NumberFormatter.format(microSieverts, decimalPlaces)} μSv/h"</span>
</code></pre></div> </div> </li> <li> <p><strong>Add tests</strong> in <code class="language-plaintext highlighter-rouge">core/common/src/commonTest/</code>:</p> <div class="language-kotlin highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nd">@Test</span>
<span class="k">fun</span> <span class="nf">radiationFormatting</span><span class="p">()</span> <span class="p">{</span>
<span class="nf">assertEquals</span><span class="p">(</span><span class="s">"0.15 μSv/h"</span><span class="p">,</span> <span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">radiation</span><span class="p">(</span><span class="mf">0.15f</span><span class="p">))</span>
<span class="nf">assertEquals</span><span class="p">(</span><span class="s">"1.23 μSv/h"</span><span class="p">,</span> <span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">radiation</span><span class="p">(</span><span class="mf">1.234f</span><span class="p">))</span>
<span class="p">}</span>
</code></pre></div> </div> </li> <li> <p><strong>Use in UI</strong> — call from any <code class="language-plaintext highlighter-rouge">commonMain</code> composable or ViewModel:</p> <div class="language-kotlin highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nc">Text</span><span class="p">(</span><span class="n">text</span> <span class="p">=</span> <span class="nc">MetricFormatter</span><span class="p">.</span><span class="nf">radiation</span><span class="p">(</span><span class="n">node</span><span class="p">.</span><span class="n">radiationLevel</span><span class="p">))</span>
</code></pre></div> </div> </li> <li> <p><strong>Run verification</strong>:</p> <div class="language-bash highlighter-rouge"><div class="highlight"><pre class="highlight"><code>./gradlew :core:common:allTests
</code></pre></div> </div> </li> </ol> <h2 id="dateformatter"> <a href="#dateformatter" class="anchor-heading" aria-labelledby="dateformatter"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> DateFormatter </h2> <p>Date and time formatting uses the <code class="language-plaintext highlighter-rouge">DateFormatter</code> <code class="language-plaintext highlighter-rouge">expect object</code> with platform-specific <code class="language-plaintext highlighter-rouge">actual</code> implementations:</p> <div class="table-wrapper"><table> <thead> <tr> <th>Function</th> <th>Output Example</th> </tr> </thead> <tbody> <tr> <td><code class="language-plaintext highlighter-rouge">formatRelativeTime()</code></td> <td>“5 min ago”</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">formatDateTime()</code></td> <td>“May 13, 2026 2:30 PM”</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">formatShortDate()</code></td> <td>“May 13”</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">formatTime()</code></td> <td>“2:30 PM”</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">formatTimeWithSeconds()</code></td> <td>“2:30:45 PM”</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">formatDate()</code></td> <td>“2026-05-13”</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">formatDateTimeShort()</code></td> <td>“5/13/26 2:30 PM”</td> </tr> </tbody> </table></div> <p>Unlike <code class="language-plaintext highlighter-rouge">MetricFormatter</code>, <code class="language-plaintext highlighter-rouge">DateFormatter</code> is declared with <code class="language-plaintext highlighter-rouge">expect</code>/<code class="language-plaintext highlighter-rouge">actual</code> (an <code class="language-plaintext highlighter-rouge">expect object</code> in <code class="language-plaintext highlighter-rouge">commonMain</code>, an <code class="language-plaintext highlighter-rouge">actual object</code> per platform) because date formatting inherently depends on platform locale APIs.</p> <h2 id="design-decisions"> <a href="#design-decisions" class="anchor-heading" aria-labelledby="design-decisions"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Design decisions </h2> <div class="table-wrapper"><table> <thead> <tr> <th>Decision</th> <th>Rationale</th> </tr> </thead> <tbody> <tr> <td>Display formatting follows the OS locale</td> <td>A number shown to a user should read the way that user writes numbers</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">formatInvariant</code> keeps a fixed <code class="language-plaintext highlighter-rouge">.</code> for machine-read values</td> <td>Interop payloads and re-parsed values break if localized</td> </tr> <tr> <td>Only temperature, wind speed, rainfall and weight convert</td> <td>The remaining metric units are universally understood in their native form</td> </tr> <tr> <td><code class="language-plaintext highlighter-rouge">object</code> singleton pattern</td> <td>Stateless utility — no instance management needed</td> </tr> </tbody> </table></div> <h2 id="related"> <a href="#related" class="anchor-heading" aria-labelledby="related"><svg viewBox="0 0 16 16" aria-hidden="true"><use xlink:href="#svg-link"></use></svg></a> Related </h2> <ul> <li><strong>User-facing docs</strong>: <a href="../user/units-and-locale">Units &amp; Locale</a> explains what end users see</li> <li><strong>Source code</strong>: <code class="language-plaintext highlighter-rouge">core/common/src/commonMain/kotlin/org/meshtastic/core/common/util/MetricFormatter.kt</code></li> <li><strong>Tests</strong>: <code class="language-plaintext highlighter-rouge">core/common/src/commonTest/kotlin/org/meshtastic/core/common/util/MetricFormatterTest.kt</code></li> </ul> </main> <hr> <footer> <footer class="site-footer"> Copyright &copy; 2026 Meshtastic LLC. Distributed under the <a href="https://www.gnu.org/licenses/gpl-3.0.html">GPL v3 License.</a> </footer> <div class="d-sm-block d-md-none"> <div class="mt-4 fs-2"> This site uses <a href="https://github.com/just-the-docs/just-the-docs">Just the Docs</a>, a documentation theme for Jekyll. </div> </div> </footer> </div> </div> <div class="search-overlay"></div> </div> </body> </html>