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Grid line registration

In this registration, the nodes are centered on the grid line intersections and the data points represent the average value in a cell of dimensions ( $x_{inc} \cdot y_{inc}$) centered on the nodes (Figure B.1). In the case of grid line registration the number of nodes are related to region and grid spacing by


\begin{displaymath}\begin{array}{ccl}
nx & = & (x_{max} - x_{min}) / x_{inc} + 1 \\
ny & = & (y_{max} - y_{min}) / y_{inc} + 1
\end{array} \end{displaymath}

which for the example in Figure B.1 yields nx = ny = 4.


  
Figure B.1: Grid line registration of data nodes
\begin{figure}\centering\epsfig{figure=eps/GMT_gridreg.eps}\end{figure}

 



Paul Wessel
1999-12-03