Generator

restriction-ratio

One function in the graphfit library, called 9 times across 3 essays. Below: what it draws at its defaults, what it draws at every value an essay asks for, the 109 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 the same 16 answers, backward stable under one reading and not under another. Every real eigenpair of an overdamped chain of 8 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.06 and 45.69, and allowing only M costs between 1.99 and 6367. At a tolerance of 10⁻¹⁵ 15 of these pairs are stable against the whole polynomial and 7 against K alone.

restriction-ratio is one function in lib/figures/graphfit.js — three approximations the data chose the shape of — support points, a restricted perturbation, and a model made of measurements. 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.

The same 16 answers, backward stable under one reading and not under anotherEvery real eigenpair of an overdamped chain of 8 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.06 and 45.69, and allowing only M costs between 1.99 and 6367. At a tolerance of 10⁻¹⁵ 15 of these pairs are stable against the whole polynomial and 7 against K alone.10⁻²10⁻¹110¹10⁻¹⁷10⁻¹⁵10⁻¹³10⁻¹¹|λ|backward error of the computed pairone residual, four denominatorspairs measured16worst, all three1.4·10⁻¹⁵worst, K alone1.8·10⁻¹⁴worst, M alone9·10⁻¹²K-only factor, low1.1high46solid: every coefficient may movedashed: only one may

Every real eigenpair of an overdamped chain of 8 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.06 and 45.69, and allowing only M costs between 1.99 and 6367. At a tolerance of 10⁻¹⁵ 15 of these pairs are stable against the whole polynomial and 7 against K alone.

n: 8

The arguments are the ones A model with no matrices behind it passes. A value drawn at the generator's defaults instead would be a picture no essay asked for and no assertion has been run against.

The same 16 answers, backward stable under one reading and not under anotherEvery real eigenpair of an overdamped chain of 8 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.06 and 45.69, and allowing only M costs between 1.99 and 6367. At a tolerance of 10⁻¹⁵ 15 of these pairs are stable against the whole polynomial and 7 against K alone.10⁻²10⁻¹110¹10⁻¹⁷10⁻¹⁵10⁻¹³10⁻¹¹|λ|backward error of the computed pairone residual, four denominatorspairs measured16worst, all three1.4·10⁻¹⁵worst, K alone1.8·10⁻¹⁴worst, M alone9·10⁻¹²K-only factor, low1.1high46solid: every coefficient may movedashed: only one may

Every real eigenpair of an overdamped chain of 8 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.06 and 45.69, and allowing only M costs between 1.99 and 6367. At a tolerance of 10⁻¹⁵ 15 of these pairs are stable against the whole polynomial and 7 against K alone.

n: 12

The arguments are the ones A perturbation that moves every coefficient passes. A value drawn at the generator's defaults instead would be a picture no essay asked for and no assertion has been run against.

The same 24 answers, backward stable under one reading and not under anotherEvery real eigenpair of an overdamped chain of 12 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.03 and 45.59, and allowing only M costs between 1.99 and 2.664·10⁴. At a tolerance of 10⁻¹⁵ 24 of these pairs are stable against the whole polynomial and 14 against K alone.10⁻³10⁻²10⁻¹110¹10⁻¹⁷10⁻¹⁵10⁻¹³10⁻¹¹|λ|backward error of the computed pairone residual, four denominatorspairs measured24worst, all three6.1·10⁻¹⁶worst, K alone2.6·10⁻¹⁴worst, M alone4.9·10⁻¹²K-only factor, low1high46solid: every coefficient may movedashed: only one may

Every real eigenpair of an overdamped chain of 12 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.03 and 45.59, and allowing only M costs between 1.99 and 2.664·10⁴. At a tolerance of 10⁻¹⁵ 24 of these pairs are stable against the whole polynomial and 14 against K alone.

n: 4

The arguments are the ones A perturbation that moves every coefficient passes. A value drawn at the generator's defaults instead would be a picture no essay asked for and no assertion has been run against.

The same 8 answers, backward stable under one reading and not under anotherEvery real eigenpair of an overdamped chain of 4 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.19 and 45.73, and allowing only M costs between 2 and 717.5. At a tolerance of 10⁻¹⁵ 8 of these pairs are stable against the whole polynomial and 3 against K alone.10⁻²10⁻¹110¹10⁻¹⁷10⁻¹⁵10⁻¹³|λ|backward error of the computed pairone residual, four denominatorspairs measured8worst, all three8.7·10⁻¹⁶worst, K alone1.8·10⁻¹⁴worst, M alone2.4·10⁻¹³K-only factor, low1.2high46solid: every coefficient may movedashed: only one may

Every real eigenpair of an overdamped chain of 4 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.19 and 45.73, and allowing only M costs between 2 and 717.5. At a tolerance of 10⁻¹⁵ 8 of these pairs are stable against the whole polynomial and 3 against K alone.

n: 6

The arguments are the ones A perturbation that moves every coefficient passes. A value drawn at the generator's defaults instead would be a picture no essay asked for and no assertion has been run against.

The same 12 answers, backward stable under one reading and not under anotherEvery real eigenpair of an overdamped chain of 6 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.1 and 45.73, and allowing only M costs between 2 and 2449. At a tolerance of 10⁻¹⁵ 12 of these pairs are stable against the whole polynomial and 5 against K alone.10⁻²10⁻¹110¹10⁻¹⁷10⁻¹⁵10⁻¹³|λ|backward error of the computed pairone residual, four denominatorspairs measured12worst, all three6.7·10⁻¹⁶worst, K alone2·10⁻¹⁴worst, M alone6.8·10⁻¹³K-only factor, low1.1high46solid: every coefficient may movedashed: only one may

Every real eigenpair of an overdamped chain of 6 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.1 and 45.73, and allowing only M costs between 2 and 2449. At a tolerance of 10⁻¹⁵ 12 of these pairs are stable against the whole polynomial and 5 against K alone.

n: 10

The arguments are the ones A perturbation that moves every coefficient passes. A value drawn at the generator's defaults instead would be a picture no essay asked for and no assertion has been run against.

The same 20 answers, backward stable under one reading and not under anotherEvery real eigenpair of an overdamped chain of 10 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.04 and 45.64, and allowing only M costs between 1.99 and 1.385·10⁴. At a tolerance of 10⁻¹⁵ 19 of these pairs are stable against the whole polynomial and 8 against K alone.10⁻²10⁻¹110¹10⁻¹⁷10⁻¹⁵10⁻¹³10⁻¹¹|λ|backward error of the computed pairone residual, four denominatorspairs measured20worst, all three3·10⁻¹⁵worst, K alone2.5·10⁻¹⁴worst, M alone4.2·10⁻¹¹K-only factor, low1high46solid: every coefficient may movedashed: only one may

Every real eigenpair of an overdamped chain of 10 masses, computed once through the first companion linearisation, and its backward error measured four ways — against perturbations of all three coefficients, of K alone, and of M alone. The unrestricted number is the one every published formula computes and it sits at the rounding level across the spectrum. Restricting the perturbation charges the same residual to less data, so it can only raise the quotient, and the factor has a closed form: (|λ|²‖M‖ + |λ|‖C‖ + ‖K‖) divided by the allowed part, checked here against the two computed numbers to 10⁻⁸. Because it carries |λ|², it is not a property of the polynomial: allowing only K to move costs between 1.04 and 45.64, and allowing only M costs between 1.99 and 1.385·10⁴. At a tolerance of 10⁻¹⁵ 19 of these pairs are stable against the whole polynomial and 8 against K alone.

What it checked while drawing

Every figure above asserted its own claims on the way to being drawn, and a claim that failed would have failed the build rather than drawn a wrong picture. Those assertions 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.

109 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.

the closed form predicts the K-only backward error at λ = -7.417 — asserted 96 times

a chain long enough to have a spectrum and short enough to draw

a chain the linearisation can afford

a linearisation has as many eigenvalues as it has rows

a positive mass

a reduction this file knows

a restriction never lowers a backward error

an inverse iterate that is a vector

an overdamped chain, whose spectrum is entirely real

at least one coefficient that is allowed to move

damping that removes energy rather than adding it

LU is for square matrices

matmul shapes agree

some real eigenpair to measure

Against the rule

It draws a decomposition and prints its residual. It calls restrictionSweep, verdictTable, and every figure above carries the badge — which residualcheck verifies by looking for it in the emitted SVG rather than by finding the call that builds one. A badge that is constructed and then left out of the body is the failure that check exists for.

Across the library: the rule bites on 214 of 382 generators — 194 print a residual and 20 are exempt with a published reason; 168 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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