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</ul></li> </ul><ul class="navbar-nav"><li class="nav-item"><form class="form-inline" role="search"> <input class="form-control" type="search" name="search-input" id="search-input" autocomplete="off" aria-label="Search site" placeholder="Search for" data-search-index="../search.json"></form></li> <li class="nav-item"><a class="external-link nav-link" href="https://github.com/tidyverse/lubridate/" aria-label="GitHub"></a></li> </ul></div> </div> </nav><div class="container template-reference-topic" id="container"> <div class="row"> <main id="main" class="col-md-9"><div class="page-header"> <img src="../logo.png" class="logo" alt=""><h1>Convert an object to a date or date-time</h1> Source: <a href="https://github.com/tidyverse/lubridate/blob/main/R/coercion.r" class="external-link"><code>R/coercion.r</code></a> <div class="d-none name"><code>as_date.Rd</code></div> </div> <div class="ref-description section level2"> Convert an object to a date or date-time </div> <div class="section level2"> <h2 id="ref-usage">Usage<a class="anchor" aria-label="anchor" href="#ref-usage"></a></h2> <div class="sourceCode"><pre class="sourceCode r"><code>as_date(x, ...) # S4 method for class 'ANY' as_date(x, ...) # S4 method for class 'POSIXt' as_date(x, tz = NULL) # S4 method for class 'numeric' as_date(x, origin = lubridate::<a href="origin.html">origin</a>) # S4 method for class 'character' as_date(x, tz = NULL, format = NULL) as_datetime(x, ...) # S4 method for class 'ANY' as_datetime(x, tz = lubridate::<a href="tz.html">tz</a>(x)) # S4 method for class 'POSIXt' as_datetime(x, tz = lubridate::<a href="tz.html">tz</a>(x)) # S4 method for class 'numeric' as_datetime(x, origin = lubridate::<a href="origin.html">origin</a>, tz = "UTC") # S4 method for class 'character' as_datetime(x, tz = "UTC", format = NULL) # S4 method for class 'Date' as_datetime(x, tz = "UTC")</code></pre></div> </div> <div class="section level2"> <h2 id="arguments">Arguments<a class="anchor" aria-label="anchor" href="#arguments"></a></h2> <dl><dt id="arg-x">x<a class="anchor" aria-label="anchor" href="#arg-x"></a></dt> <dd>a vector of <a href="https://rdrr.io/r/base/DateTimeClasses.html" class="external-link">POSIXt</a>, numeric or character objects</dd> <dt id="arg--">...<a class="anchor" aria-label="anchor" href="#arg--"></a></dt> <dd>further arguments to be passed to specific methods (see above).</dd> <dt id="arg-tz">tz<a class="anchor" aria-label="anchor" href="#arg-tz"></a></dt> <dd>a time zone name (default: time zone of the POSIXt object <code>x</code>). See <code><a href="https://rdrr.io/r/base/timezones.html" class="external-link">OlsonNames()</a></code>.</dd> <dt id="arg-origin">origin<a class="anchor" aria-label="anchor" href="#arg-origin"></a></dt> <dd>a Date object, or something which can be coerced by <code>as.Date(origin, ...)</code> to such an object (default: the Unix epoch of "1970-01-01"). Note that in this instance, <code>x</code> is assumed to reflect the number of days since <code>origin</code> at <code>"UTC"</code>.</dd> <dt id="arg-format">format<a class="anchor" aria-label="anchor" href="#arg-format"></a></dt> <dd>format argument for character methods. When supplied parsing is performed by <code>parse_date_time(x, orders = formats, exact = TRUE)</code>. Thus, multiple formats are supported and are tried in turn.</dd> </dl></div> <div class="section level2"> <h2 id="value">Value<a class="anchor" aria-label="anchor" href="#value"></a></h2> a vector of <a href="date_utils.html">Date</a> objects corresponding to <code>x</code>. </div> <div class="section level2"> <h2 id="compare-to-base-r">Compare to base R<a class="anchor" aria-label="anchor" href="#compare-to-base-r"></a></h2> These are drop in replacements for <code><a href="https://rdrr.io/r/base/as.Date.html" class="external-link">as.Date()</a></code> and <code><a href="https://rdrr.io/r/base/as.POSIXlt.html" class="external-link">as.POSIXct()</a></code>, with a few tweaks to make them work more intuitively. <ul><li>Called on a <code>POSIXct</code> object, <code>as_date()</code> uses the tzone attribute of the object to return the same date as indicated by the printed representation of the object. This differs from as.Date, which ignores the attribute and uses only the tz argument to <code><a href="https://rdrr.io/r/base/as.Date.html" class="external-link">as.Date()</a></code> ("UTC" by default).</li> <li>Both functions provide a default origin argument for numeric vectors.</li> <li>Both functions will generate NAs for invalid date format. Valid formats are those described by ISO8601 standard. A warning message will provide a count of the elements that were not converted.</li> <li><code>as_datetime()</code> defaults to using UTC.</li> </ul></div> <div class="section level2"> <h2 id="ref-examples">Examples<a class="anchor" aria-label="anchor" href="#ref-examples"></a></h2> <div class="sourceCode"><pre class="sourceCode r"><code>dt_utc <- <a href="ymd_hms.html">ymd_hms</a>("2010-08-03 00:50:50") dt_europe <- <a href="ymd_hms.html">ymd_hms</a>("2010-08-03 00:50:50", tz = "Europe/London") <a href="https://rdrr.io/r/base/c.html" class="external-link">c</a>(as_date(dt_utc), <a href="https://rdrr.io/r/base/as.Date.html" class="external-link">as.Date</a>(dt_utc)) #> [1] "2010-08-03" "2010-08-03" <a href="https://rdrr.io/r/base/c.html" class="external-link">c</a>(as_date(dt_europe), <a href="https://rdrr.io/r/base/as.Date.html" class="external-link">as.Date</a>(dt_europe)) #> [1] "2010-08-03" "2010-08-02" ## need not supply origin as_date(10) #> [1] "1970-01-11" ## Will replace invalid date format with NA dt_wrong <- <a href="https://rdrr.io/r/base/c.html" class="external-link">c</a>("2009-09-29", "2012-11-29", "2015-29-12") as_date(dt_wrong) #> Warning: 1 failed to parse. #> [1] "2009-09-29" "2012-11-29" NA </code></pre></div> </div> </main><aside class="col-md-3"><nav id="toc" aria-label="Table of contents"><h2>On this page</h2> </nav></aside></div> </div> <footer><div class="container"> <div class="pkgdown-footer-left"> Developed by Vitalie Spinu, Garrett Grolemund, <a href="https://hadley.nz" class="external-link">Hadley Wickham</a>. </div> <div class="pkgdown-footer-right"> Site built with <a href="https://pkgdown.r-lib.org/" class="external-link">pkgdown</a> 2.1.1. </div> </div></footer></body></html>