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<table width="100%" summary="page for cov {SparkR}"><tr><td>cov {SparkR}</td><td style="text-align: right;">R Documentation</td></tr></table>
<h2>cov</h2>
<h3>Description</h3>
<p>Compute the covariance between two expressions.
</p>
<h3>Usage</h3>
<pre>
cov(x, ...)
covar_samp(col1, col2)
covar_pop(col1, col2)
## S4 method for signature 'characterOrColumn'
cov(x, col2)
## S4 method for signature 'characterOrColumn,characterOrColumn'
covar_samp(col1, col2)
## S4 method for signature 'characterOrColumn,characterOrColumn'
covar_pop(col1, col2)
## S4 method for signature 'SparkDataFrame'
cov(x, colName1, colName2)
</pre>
<h3>Arguments</h3>
<table summary="R argblock">
<tr valign="top"><td><code>x</code></td>
<td>
<p>a Column or a SparkDataFrame.</p>
</td></tr>
<tr valign="top"><td><code>...</code></td>
<td>
<p>additional argument(s). If <code>x</code> is a Column, a Column
should be provided. If <code>x</code> is a SparkDataFrame, two column names should
be provided.</p>
</td></tr>
<tr valign="top"><td><code>col1</code></td>
<td>
<p>the first Column.</p>
</td></tr>
<tr valign="top"><td><code>col2</code></td>
<td>
<p>the second Column.</p>
</td></tr>
<tr valign="top"><td><code>colName1</code></td>
<td>
<p>the name of the first column</p>
</td></tr>
<tr valign="top"><td><code>colName2</code></td>
<td>
<p>the name of the second column</p>
</td></tr>
</table>
<h3>Details</h3>
<p><code>cov</code>: Compute the sample covariance between two expressions.
</p>
<p><code>covar_sample</code>: Alias for <code>cov</code>.
</p>
<p><code>covar_pop</code>: Computes the population covariance between two expressions.
</p>
<p><code>cov</code>: When applied to SparkDataFrame, this calculates the sample covariance of two
numerical columns of <em>one</em> SparkDataFrame.
</p>
<h3>Value</h3>
<p>The covariance of the two columns.
</p>
<h3>Note</h3>
<p>cov since 1.6.0
</p>
<p>covar_samp since 2.0.0
</p>
<p>covar_pop since 2.0.0
</p>
<p>cov since 1.6.0
</p>
<h3>See Also</h3>
<p>Other aggregate functions: <code><a href="avg.html">avg</a></code>,
<code><a href="column_aggregate_functions.html">column_aggregate_functions</a></code>,
<code><a href="corr.html">corr</a></code>, <code><a href="count.html">count</a></code>,
<code><a href="first.html">first</a></code>, <code><a href="last.html">last</a></code>
</p>
<p>Other stat functions: <code><a href="approxQuantile.html">approxQuantile</a></code>,
<code><a href="corr.html">corr</a></code>, <code><a href="crosstab.html">crosstab</a></code>,
<code><a href="freqItems.html">freqItems</a></code>, <code><a href="sampleBy.html">sampleBy</a></code>
</p>
<h3>Examples</h3>
<pre><code class="r">## Not run:
##D df &lt;- createDataFrame(cbind(model = rownames(mtcars), mtcars))
##D head(select(df, cov(df$mpg, df$hp), cov(&quot;mpg&quot;, &quot;hp&quot;),
##D covar_samp(df$mpg, df$hp), covar_samp(&quot;mpg&quot;, &quot;hp&quot;),
##D covar_pop(df$mpg, df$hp), covar_pop(&quot;mpg&quot;, &quot;hp&quot;)))
## End(Not run)
## Not run:
##D cov(df, &quot;mpg&quot;, &quot;hp&quot;)
##D cov(df, df$mpg, df$hp)
## End(Not run)
</code></pre>
<hr /><div style="text-align: center;">[Package <em>SparkR</em> version 2.3.2 <a href="00Index.html">Index</a>]</div>
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