annotate +time/+cdiff/cdiff.m @ 1347:ac54767ae1fb feature/poroelastic tip

Add interface, not fully compatible.
author Martin Almquist <martin.almquist@it.uu.se>
date Tue, 30 Apr 2024 14:58:35 +0200
parents 48b6fb693025
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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1 % Takes a step of
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2 % v_tt = Dv+Ev_t+S
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3 %
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4 % 1/k^2 * (v_next - 2v + v_prev) = Dv + E 1/(2k)(v_next - v_prev) + S
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5 %
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6 function [v_next, v] = cdiff(v, v_prev, k, D, E, S)
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7 % 1/k^2 * (v_next - 2v + v_prev) = Dv + E 1/(2k)(v_next - v_prev) + S
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8 % ekv to
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9 % A v_next = B v + C v_prev + S
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10 I = speye(size(D));
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11 A = 1/k^2 * I - 1/(2*k)*E;
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12 B = 2/k^2 * I + D;
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13 C = -1/k^2 * I - 1/(2*k)*E;
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14
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15 v_next = A\(B*v + C*v_prev + S);
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16 end