A Fourth-Order Block-Grid Method for Solving Laplace's Equation on a Staircase Polygon with Boundary Functions in <svg     style="vertical-align:-0.306pt;width:36.6875px;" id="M1" height="22.4375" version="1.1" viewBox="0 0 36.6875 22.4375" width="36.6875"  xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg">
	
		
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</svg> in the “singular” part.</table>

Abstract and Applied Analysis

fig9

Figure 9

Figure 9: A Fourth-Order Block-Grid Method for Solving Laplace's Equation on a Staircase Polygon with Boundary Functions in <svg     style="vertical-align:-0.306pt;width:36.6875px;" id="M1" height="22.4375" version="1.1" viewBox="0 0 36.6875 22.4375" width="36.6875"  xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg">
	
		
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