Generator

One system, 60 ways to remove its kernel, and 10.5× between them

One function in the graphlap library, called 6 times across 1 essay. Below: what it draws at its defaults, what it draws at every value an essay asks for, the 9 claims it put to the test while drawing them, and where it stands against the rule this site is named for.

At its defaults it draws one system, 60 ways to remove its kernel, and 10.5× between them. A Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the preferential 60: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 53, of degree 2, gives κ = 926.22; grounding vertex 3, of degree 17, gives 88.226 — a factor of 10.5 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.

grounding-choice is one function in lib/figures/graphlap.js — the matrix a graph makes — row sums that are exactly zero, a count that is a threshold, and a partition with no vector. 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.

One system, 60 ways to remove its kernel, and 10.5× between themA Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the preferential 60: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 53, of degree 2, gives κ = 926.22; grounding vertex 3, of degree 17, gives 88.226 — a factor of 10.5 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.25811141710²10³degree of the grounded vertexcondition number of what is left88.23, the best choicea parameter nobody setsvertices tried60best κ88at degree17worst κ926at degree2spread10one row and column deletedand it matters which

A Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the preferential 60: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 53, of degree 2, gives κ = 926.22; grounding vertex 3, of degree 17, gives 88.226 — a factor of 10.5 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.

family: "star", n: 30

The arguments are the ones The vertex nobody solves for passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

One system, 30 ways to remove its kernel, and 898× between themA Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the star 30: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 1, of degree 1, gives κ = 898; grounding vertex 0, of degree 29, gives 1 — a factor of 898 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.1611162126110¹10²10³degree of the grounded vertexcondition number of what is left1, the best choicea parameter nobody setsvertices tried30best κ1at degree29worst κ898at degree1spread898one row and column deletedand it matters which

A Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the star 30: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 1, of degree 1, gives κ = 898; grounding vertex 0, of degree 29, gives 1 — a factor of 898 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.

family: "skewed", n: 60

The arguments are the ones The vertex nobody solves for passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

One system, 60 ways to remove its kernel, and 10.5× between themA Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the preferential 60: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 53, of degree 2, gives κ = 926.22; grounding vertex 3, of degree 17, gives 88.226 — a factor of 10.5 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.25811141710²10³degree of the grounded vertexcondition number of what is left88.23, the best choicea parameter nobody setsvertices tried60best κ88at degree17worst κ926at degree2spread10one row and column deletedand it matters which

A Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the preferential 60: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 53, of degree 2, gives κ = 926.22; grounding vertex 3, of degree 17, gives 88.226 — a factor of 10.5 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.

family: "grid"

The arguments are the ones The vertex nobody solves for passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

One system, 64 ways to remove its kernel, and 3.02× between themA Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the grid 8×8: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 7, of degree 2, gives κ = 589.89; grounding vertex 28, of degree 4, gives 195.26 — a factor of 3.021 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.23410²10³degree of the grounded vertexcondition number of what is left195.3, the best choicea parameter nobody setsvertices tried64best κ195at degree4worst κ590at degree2spread3one row and column deletedand it matters which

A Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the grid 8×8: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 7, of degree 2, gives κ = 589.89; grounding vertex 28, of degree 4, gives 195.26 — a factor of 3.021 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.

family: "path"

The arguments are the ones The vertex nobody solves for passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

One system, 60 ways to remove its kernel, and 3.81× between themA Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the path 60: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 59, of degree 1, gives κ = 5735.6; grounding vertex 30, of degree 2, gives 1504.4 — a factor of 3.813 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.1210³10⁴degree of the grounded vertexcondition number of what is left1504, the best choicea parameter nobody setsvertices tried60best κ1504at degree2worst κ5736at degree1spread3.8one row and column deletedand it matters which

A Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the path 60: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 59, of degree 1, gives κ = 5735.6; grounding vertex 30, of degree 2, gives 1504.4 — a factor of 3.813 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.

family: "barbell"

The arguments are the ones The vertex nobody solves for passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

One system, 60 ways to remove its kernel, and 1.1× between themA Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the barbell 30: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 31, of degree 29, gives κ = 1053.9; grounding vertex 30, of degree 30, gives 959 — a factor of 1.099 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.293010³degree of the grounded vertexcondition number of what is left959, the best choicea parameter nobody setsvertices tried60best κ959at degree30worst κ1054at degree29spread1.1one row and column deletedand it matters which

A Laplacian is singular, so a solve has to remove its kernel, and the usual way is to delete one row and column — grounding a vertex, in the electrical reading. Which vertex is a free parameter that no account of the method mentions, and it is set by whichever index the code happens to drop. Every point here is one choice on the barbell 30: the condition number of the resulting positive definite matrix against the degree of the vertex removed. Grounding vertex 31, of degree 29, gives κ = 1053.9; grounding vertex 30, of degree 30, gives 959 — a factor of 1.099 between two ways of solving the identical problem. The trend is that a high-degree vertex is the better ground, which has a reading: grounding a vertex fixes its potential, and fixing the potential of something the rest of the graph is strongly attached to constrains more of the graph.

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.

9 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 connected graph, which is what grounding one vertex needs

a family the library builds

a graph small enough to ground at every vertex in turn

a graph with at least two vertices

a positive weight

every endpoint inside the vertex set

every grounded Laplacian is positive definite

no edge given twice

no self-loop

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.

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