Generator

probe-ceiling

One function in the nlevp library, called 12 times across 3 essays. Below: what it draws at its defaults, what it draws at every value an essay asks for, the 5 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 how many eigenvalues a contour method can return: the probe block is a ceiling and does not say so. Beyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 4 eigenvalues inside |z| = 4: the rank is 1, 2, 3, 4, 4 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 4. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.

probe-ceiling is one function in lib/figures/nlevp.js — infinitely many eigenvalues — a contour that counts, and the probe block that is a ceiling. 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.

How many eigenvalues a contour method can return: the probe block is a ceiling and does not say soBeyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 4 eigenvalues inside |z| = 4: the rank is 1, 2, 3, 4, 4 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 4. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.1 probe12 probes23 probes34 probes45 probes44 insidea ceiling nothing announceseigenvalues inside4rank at 1 probe1rank at 5 probes4the binding ceiling4the residuals are smalland half the answer is missing

Beyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 4 eigenvalues inside |z| = 4: the rank is 1, 2, 3, 4, 4 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 4. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.

radius: 4

The arguments are the ones A problem with infinitely many eigenvalues 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.

How many eigenvalues a contour method can return: the probe block is a ceiling and does not say soBeyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 4 eigenvalues inside |z| = 4: the rank is 1, 2, 3, 4, 4 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 4. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.1 probe12 probes23 probes34 probes45 probes44 insidea ceiling nothing announceseigenvalues inside4rank at 1 probe1rank at 5 probes4the binding ceiling4the residuals are smalland half the answer is missing

Beyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 4 eigenvalues inside |z| = 4: the rank is 1, 2, 3, 4, 4 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 4. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.

radius: 2

The arguments are the ones A problem with infinitely many eigenvalues 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.

How many eigenvalues a contour method can return: the probe block is a ceiling and does not say soBeyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 2 eigenvalues inside |z| = 2: the rank is 1, 2, 2, 2, 2 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 2. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.1 probe12 probes23 probes24 probes25 probes22 insidea ceiling nothing announceseigenvalues inside2rank at 1 probe1rank at 5 probes2the binding ceiling2the residuals are smalland half the answer is missing

Beyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 2 eigenvalues inside |z| = 2: the rank is 1, 2, 2, 2, 2 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 2. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.

radius: 5

The arguments are the ones A problem with infinitely many eigenvalues 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.

How many eigenvalues a contour method can return: the probe block is a ceiling and does not say soBeyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 12 eigenvalues inside |z| = 5: the rank is 1, 2, 3, 4, 4 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 4, which is the SIZE of the problem rather than the number of eigenvalues — a second ceiling, because an 4 × ℓ block cannot have rank above 4 whatever is inside the contour. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.1 probe12 probes23 probes34 probes45 probes44 rowsa ceiling nothing announceseigenvalues inside12rank at 1 probe1rank at 5 probes4the binding ceiling4the residuals are smalland half the answer is missing

Beyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 12 eigenvalues inside |z| = 5: the rank is 1, 2, 3, 4, 4 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 4, which is the SIZE of the problem rather than the number of eigenvalues — a second ceiling, because an 4 × ℓ block cannot have rank above 4 whatever is inside the contour. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.

radius: 3

The arguments are the ones A problem with infinitely many eigenvalues 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.

How many eigenvalues a contour method can return: the probe block is a ceiling and does not say soBeyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 3 eigenvalues inside |z| = 3: the rank is 1, 2, 3, 3, 3 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 3. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.1 probe12 probes23 probes34 probes35 probes33 insidea ceiling nothing announceseigenvalues inside3rank at 1 probe1rank at 5 probes3the binding ceiling3the residuals are smalland half the answer is missing

Beyn's method probes the contour with a random 4 × ℓ block V and reads the eigenvalues out of the rank of ∮T(z)⁻¹V dz. That rank is at most ℓ whatever is inside, so a probe block narrower than the number of eigenvalues present returns ℓ of them — with small residuals, and with nothing in the returned object to say that there were more. Measured with 3 eigenvalues inside |z| = 3: the rank is 1, 2, 3, 3, 3 at ℓ = 1, 2, 3, 4, 5, rising with the probe count and then stopping at 3. A caller who asked for two gets two. The counting integral is the check that says so, and it costs one more pass round the same contour.

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.

5 distinct claims across 5 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 contour with something inside it

a size the contour integrals can afford

a size the probes can be run at

LU is for square matrices

the rank is the smallest of the probe count, the count inside and the size

Against the rule

It draws a decomposition and prints its residual. It calls beynRank, countInside, 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 173 of 325 generators — 158 print a residual and 15 are exempt with a published reason; 152 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.

The whole library · All essays · What must fail