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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<table>Dependence of the approximate solutions for the boundary functions from <svg height="17.049999" id="M132" style="vertical-align:-0.23206pt" version="1.1" viewbox="0 0 28 17.049999" width="28" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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Abstract and Applied Analysis

fig1

Figure 1

Figure 1: 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">
	
		
			<g transform="matrix(.022,-0,0,-.022,.062,22)"><path id="x1D436" d="M682 629q-1 -16 -1.5 -72t-2.5 -86l-31 -4q-5 92 -51 129t-139 37q-100 0 -177 -49t-116 -125t-39 -162q0 -122 66 -201t182 -79q83 0 137 42.5t112 128.5l26 -15q-12 -31 -42.5 -88t-45.5 -75q-139 -27 -199 -27q-148 0 -243 81.5t-95 226.5q0 173 129.5 274.5
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