One sweep cut, two conductances: 0.1235 and 0.04
At its defaults it draws one sweep cut, two conductances: 0.1235 and 0.04. Every prefix of the sweep over the second eigenvector of Chung's Laplacian, on two blocks with 1 arc back at 24 vertices, with two quantities plotted for each. The circulation conductance is the probability that a step of the stationary walk crosses the cut, divided by the smaller side's stationary mass; the arc conductance is the weight of arcs crossing it, divided by the smaller side's degree. At the best cut they are 0.1235 and 0.04, a factor of 3.09 apart. The shaded band is Cheeger's, λ₂/2 = 0.03309 to √(2λ₂) = 0.3638 with λ₂ = 0.06619, and it is a statement about the first quantity only. Reading it as a statement about the second is the substitution this figure exists to separate.
two-conductances is one function in lib/figures/digraph.js —
arrows — a laplacian that is not symmetric, and the walk that has to be computed before it can be. Everything below came out of it during this build, at
arguments taken from the essays rather than invented for this page. A figure here is the
figure a reader meets in an essay, and if the generator changes, this page changes with it.
At its defaults
Drawn even though every essay passes arguments — which on this site is every essay, at 100% of placements since the standard pass. A default nothing exercises is a trap for the next essay to call this with none, and this is the page where a default that has drifted from the figures around it becomes visible.
Every prefix of the sweep over the second eigenvector of Chung's Laplacian, on two blocks with 1 arc back at 24 vertices, with two quantities plotted for each. The circulation conductance is the probability that a step of the stationary walk crosses the cut, divided by the smaller side's stationary mass; the arc conductance is the weight of arcs crossing it, divided by the smaller side's degree. At the best cut they are 0.1235 and 0.04, a factor of 3.09 apart. The shaded band is Cheeger's, λ₂/2 = 0.03309 to √(2λ₂) = 0.3638 with λ₂ = 0.06619, and it is a statement about the first quantity only. Reading it as a statement about the second is the substitution this figure exists to separate.
n: 24, back: 1
The arguments are the ones A conductance the arcs do not measure passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.
Every prefix of the sweep over the second eigenvector of Chung's Laplacian, on two blocks with 1 arc back at 24 vertices, with two quantities plotted for each. The circulation conductance is the probability that a step of the stationary walk crosses the cut, divided by the smaller side's stationary mass; the arc conductance is the weight of arcs crossing it, divided by the smaller side's degree. At the best cut they are 0.1235 and 0.04, a factor of 3.09 apart. The shaded band is Cheeger's, λ₂/2 = 0.03309 to √(2λ₂) = 0.3638 with λ₂ = 0.06619, and it is a statement about the first quantity only. Reading it as a statement about the second is the substitution this figure exists to separate.
back: 8
The arguments are the ones A conductance the arcs do not measure passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.
Every prefix of the sweep over the second eigenvector of Chung's Laplacian, on two blocks with 8 arcs back at 24 vertices, with two quantities plotted for each. The circulation conductance is the probability that a step of the stationary walk crosses the cut, divided by the smaller side's stationary mass; the arc conductance is the weight of arcs crossing it, divided by the smaller side's degree. At the best cut they are 0.1458 and 0.5385, a factor of 3.69 apart. The shaded band is Cheeger's, λ₂/2 = 0.05806 to √(2λ₂) = 0.4819 with λ₂ = 0.1161, and it is a statement about the first quantity only. Reading it as a statement about the second is the substitution this figure exists to separate.
back: 3
The arguments are the ones A conductance the arcs do not measure passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.
Every prefix of the sweep over the second eigenvector of Chung's Laplacian, on two blocks with 3 arcs back at 24 vertices, with two quantities plotted for each. The circulation conductance is the probability that a step of the stationary walk crosses the cut, divided by the smaller side's stationary mass; the arc conductance is the weight of arcs crossing it, divided by the smaller side's degree. At the best cut they are 0.07682 and 0.1481, a factor of 1.93 apart. The shaded band is Cheeger's, λ₂/2 = 0.03444 to √(2λ₂) = 0.3711 with λ₂ = 0.06887, and it is a statement about the first quantity only. Reading it as a statement about the second is the substitution this figure exists to separate.
back: 6
The arguments are the ones A conductance the arcs do not measure passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.
Every prefix of the sweep over the second eigenvector of Chung's Laplacian, on two blocks with 6 arcs back at 24 vertices, with two quantities plotted for each. The circulation conductance is the probability that a step of the stationary walk crosses the cut, divided by the smaller side's stationary mass; the arc conductance is the weight of arcs crossing it, divided by the smaller side's degree. At the best cut they are 0.1369 and 0.375, a factor of 2.74 apart. The shaded band is Cheeger's, λ₂/2 = 0.05558 to √(2λ₂) = 0.4715 with λ₂ = 0.1112, and it is a statement about the first quantity only. Reading it as a statement about the second is the substitution this figure exists to separate.
n: 30, back: 2
The arguments are the ones A conductance the arcs do not measure passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.
Every prefix of the sweep over the second eigenvector of Chung's Laplacian, on two blocks with 2 arcs back at 30 vertices, with two quantities plotted for each. The circulation conductance is the probability that a step of the stationary walk crosses the cut, divided by the smaller side's stationary mass; the arc conductance is the weight of arcs crossing it, divided by the smaller side's degree. At the best cut they are 0.05784 and 0.2, a factor of 3.46 apart. The shaded band is Cheeger's, λ₂/2 = 0.02152 to √(2λ₂) = 0.2934 with λ₂ = 0.04303, and it is a statement about the first quantity only. Reading it as a statement about the second is the substitution this figure exists to separate.
What it checked while drawing
Every figure above checked its own claims on the way to being drawn, and a claim that failed
would have stopped the picture rather than shipped a wrong one. Those checks used to leave
no trace at all: a passing one returned true and the only evidence the figure had
checked anything was that nothing crashed. The list below is what they actually said, collected
by running this generator with an observer installed — not a description of
what it is believed to check.
14 distinct claims across 6 sets of arguments, grouped below by shape — because most of them are one sentence with a different number in it, and how many separate times that sentence was put to the test is the informative part.
a digraph the sweep is drawn over
a digraph with at least two vertices
and every entry of it is nonnegative, as a probability must be
arcs inside the vertex set
Cheeger's inequality holds for the circulation conductance
Chung's Laplacian is symmetric to the rounding level
how many arcs run back across the cut
Jacobi needs a symmetric matrix
no repeated arc
no self-loops
positive arc weights
the assertion refuses a counterexample
the power iteration reached a stationary vector
the two conductances of one cut differ by more than a factor of two on the reference graph
Against the rule
The rule does not apply to it. It factorises nothing, so there is no residual it could be withholding. That is worth stating rather than leaving blank: a site that reported the rule as satisfied by every generator would be counting mostly generators the rule never reached.
Across the library: the rule bites on 217
of 397 generators —
199 print a residual and
18 are exempt with a published reason;
180 factorise nothing.
Read from lib/residual-rule.js, which is the same body the gate enforces from,
and the gate's last check fails the build if this page and it disagree about any generator.
Where it is called
Changing this generator changes every figure on this list. That is what makes the list worth publishing rather than keeping in a check script.