51 lines
1.1 KiB
Plaintext
51 lines
1.1 KiB
Plaintext
var (w, h) = (10, 10)
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var v = h.of { w.of(0) } # voltage
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var f = h.of { w.of(0) } # fixed condition
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var d = h.of { w.of(0) } # diff
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var n = [] # neighbors
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for i in ^h {
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for j in (1 ..^ w ) { n[i][j] := [] << [i, j-1] }
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for j in (0 ..^ w-1) { n[i][j] := [] << [i, j+1] }
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}
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for j in ^w {
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for i in (1 ..^ h ) { n[i][j] := [] << [i-1, j] }
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for i in (0 ..^ h-1) { n[i][j] := [] << [i+1, j] }
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}
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func set_boundary {
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f[1][1] = 1; f[6][7] = -1;
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v[1][1] = 1; v[6][7] = -1;
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}
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func calc_diff {
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var total_diff = 0
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for i,j in (^h ~X ^w) {
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var w = n[i][j].map { |a| v.dig(a...) }.sum
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d[i][j] = (w = (v[i][j] - w/n[i][j].len))
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f[i][j] || (total_diff += w*w)
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}
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total_diff
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}
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func iter {
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var diff = 1
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while (diff > 1e-24) {
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set_boundary()
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diff = calc_diff()
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for i,j in (^h ~X ^w) {
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v[i][j] -= d[i][j]
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}
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}
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var current = 3.of(0)
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for i,j in (^h ~X ^w) {
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current[ f[i][j] ] += (d[i][j] * n[i][j].len)
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}
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(current[1] - current[-1]) / 2
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}
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say "R = #{2 / iter()}"
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