EVOLUTION-MANAGER

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<table width="100%" summary="page for is.regular {zoo}"><tr><td>is.regular {zoo}</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Check Regularity of a Series</h2>

<h3>Description</h3>

<p><code>is.regular</code> is a regular function for checking whether a series of ordered observations
has an underlying regularity or is even strictly regular.
</p>

<h3>Usage</h3>

<pre>
is.regular(x, strict = FALSE)
</pre>

<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>x</code></td>
<td>
<p>an object (representing a series of ordered observations).</p>
</td></tr>
<tr valign="top"><td><code>strict</code></td>
<td>
<p>logical. Should strict regularity be checked? See details.</p>
</td></tr>
</table>

<h3>Details</h3>

<p>A time series can either be irregular (unequally spaced), strictly regular (equally spaced)
or have an underlying regularity, i.e., be created from a regular series by
omitting some observations. Here, the latter property is called <em>regular</em>.
Consequently, regularity follows from strict regularity but not vice versa.
</p>
<p><code>is.regular</code> is a generic function for checking regularity (default) or
strict regularity. Currently, it has methods for <code>"ts"</code> objects (which are
always strictly regular), <code>"zooreg"</code> objects (which are at least regular),
<code>"zoo"</code> objects (which can be either irregular, regular or even strictly regular)
and a default method. The latter coerces <code>x</code> to <code>"zoo"</code> before checking
its regularity. 
</p>

<h3>Value</h3>

<p>A logical is returned indicating whether <code>x</code> is (strictly) regular.
</p>

<p><code><a href="zooreg.html">zooreg</a></code>, <code><a href="zoo.html">zoo</a></code></p>

<h3>Examples</h3>

<pre>
## checking of a strictly regular zoo series
z &lt;- zoo(1:10, seq(2000, 2002.25, by = 0.25), frequency = 4)
z
class(z)
frequency(z) ## extraction of frequency attribute
is.regular(z)
is.regular(z, strict = TRUE)
## by omitting observations, the series is not strictly regular
is.regular(z[-3])
is.regular(z[-3], strict = TRUE)

## checking of a plain zoo series without frequency attribute
## which is in fact regular
z &lt;- zoo(1:10, seq(2000, 2002.25, by = 0.25))
z
class(z)
frequency(z) ## data driven computation of frequency
is.regular(z)
is.regular(z, strict = TRUE)
## by omitting observations, the series is not strictly regular
is.regular(z[-3])
is.regular(z[-3], strict = TRUE)

suppressWarnings(RNGversion("3.5.0"))
set.seed(1)

## checking of an irregular zoo series
z &lt;- zoo(1:10, rnorm(10))
z
class(z)
frequency(z) ## attempt of data-driven frequency computation
is.regular(z)
is.regular(z, strict = TRUE)
</pre>

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