<!--Copyright (C) 1988-2005 by the Institute of Global Environment and Society (IGES). See file COPYRIGHT for more information.--> <html> <title>GrADS Function: scorr</title> <body bgcolor="e0f0ff" text="#000000"> <h2><b>scorr()</b></h2> <p> This function calculates the spatial correlation between two variables over an X-Y domain. It returns a single number. The syntax is: <ul> <code>scorr(<i>expr1, expr2, xdim1, xdim2, ydim1, ydim2</i>)</code> </ul> <p> where: <p> <ul> <code><i>expr1</i> </code>- any valid GrADS expression <br> <code><i>expr2</i> </code>- any valid GrADS expression <br> <code><i>xdim1</i> </code>- starting X dimension expression <br> <code><i>xdim2</i> </code>- ending X dimension expression <br> <code><i>ydim1</i> </code>- starting Y dimension expression <br> <code><i>ydim2</i> </code>- ending Y dimension expression <br> </ul> <p> For global averaging, a shorthand may be used: <ul> <code>scorr(<i>expr1, expr2</i>, global)</code> or<br> <code>scorr(<i>expr1, expr2</i>, g)</code> </ul> is the same as <ul> <code>scorr(<i>expr1, expr2</i>, lon=0, lon=360, lat=-90, lat=90)</code> </ul> <p> <H3>Usage Note</H3> <p> <ol> <li><code>scorr</code> may be used in conjunction with <a href="gradfunctloop.html"><code>tloop</code></a> or <a href="gradcomddefine.html"><code>define</code></a> to create time series or time/height plots. <p> <li><code>scorr</code> assumes that the world coordinates are longitude in the X dimension and latitude in the Y dimension, and does weighting in the latitude dimension by the delta of the sin of the latitudes. Weighting is also performed appropriately for unequally spaced grids. </ol> <p> <H3>Examples</H3> <p> This example calculates the correlation between the surface temperature and the latent heat flux over the tropical Pacific: <p> <pre> set lat -10 10 set lon 120 280 d scorr(tsfc, lhtfl, lon=120, lon=280, lat=-10, lat=10) </pre> </body> </html>
