Source: https://jmrplens.github.io/phonometry/reference/api/solids/catalogue/ Solid materials as one published table prints them. A caller who needs a Young's modulus for plasterboard has two bad options and one good one. They can type a number they half remember, or they can open a book and copy a row by hand into their script, which is the same thing with extra steps. The good one is to read the row from a catalogue that says which page it came from, and that is what this module is. What it is careful about ------------------------ A materials table is not a list of measurements. Hopkins Table A2 marks most of its Poisson ratios and internal loss factors with a footnote that reads, in full, "Estimate", and it prints some of its densities as a range rather than a number, some of its loss factors as an upper bound, and one of its wave speeds with a note that the material is orthotropic and the figure quoted is an effective value. A catalogue that flattened all of that into floats would be claiming twenty-five measured Poisson ratios where the page offers four. So every row carries what the cell actually said: [`SolidMaterial.basis`](/phonometry/reference/api/solids/catalogue/#solidmaterial) holds `"estimated"` for each field the page marks as an estimate, which [`basis_of`](/phonometry/reference/api/io/io/#cataloguerowbasis_of) reads back, [`SolidMaterial.ranges`](/phonometry/reference/api/solids/catalogue/#solidmaterial) carries the seven cells printed as an interval (two densities, two speeds and three loss factors), [`SolidMaterial.bounded_above`](/phonometry/reference/api/solids/catalogue/#solidmaterial) names the two of those loss factors the page prints as an upper bound rather than a band, and [`SolidMaterial.attributed_to`](/phonometry/reference/api/solids/catalogue/#solidmaterial) carries the per-cell credit for the rows whose columns come from different authors. A field the table leaves empty is `None` and not a guess. Where the rows live ------------------- In `solids/data/hopkins-2007-table-a2.json`, one record per material, read at import through the package-data reader in `phonometry._internal`. Rows are data: keeping them in a file means a second table is a second file rather than a longer literal, means a changed digit is one line of a diff, and means the citation is written once, in the file that holds the rows it belongs to. The provenance gate reads it from there too, so the comment above the constant and the page it names cannot drift apart. What it is not -------------- It is not a specification. Block densities vary by manufacturer, boards vary by batch, and Hopkins says as much by printing ranges where a range is what is known. Use a row to reproduce a worked example, to sanity-check a measurement, or to get an order of magnitude; use a measurement for anything that has to be right. > Auto-generated from the source docstrings by `scripts/generate_api_docs.py` (`make api-docs`). Do not edit by hand. ## PUBLISHED_SOLIDS *Constant* (`mapping`). ## SolidMaterial ```python SolidMaterial( *, name: str, source: str, table: str = '', variant: str = '', basis: Mapping[str, str] = ..., approximate: frozenset[str] = frozenset(), derived: Mapping[str, str] = ..., converted: Mapping[str, tuple[str, str]] = ..., carried: Mapping[str, str] = ..., ranges: Mapping[str, tuple[float | None, float | None]] = ..., bounded_above: frozenset[str] = frozenset(), bounded_below: frozenset[str] = frozenset(), reported: Mapping[str, tuple[float | tuple[float, float], ...]] = ..., unquantified: Mapping[str, str] = ..., uncertainty: Mapping[str, float] = ..., not_derivable: Mapping[str, str] = ..., misprinted: Mapping[str, str] = ..., attributed_to: Mapping[str, str] = ..., group: str = '', note: str = '', density_kg_m3: float | None = None, youngs_modulus_pa: float | None = None, shear_modulus_pa: float | None = None, poisson_ratio: float | None = None, longitudinal_speed_m_s: float | None = None, bar_longitudinal_speed_m_s: float | None = None, plate_longitudinal_speed_m_s: float | None = None, bulk_longitudinal_speed_m_s: float | None = None, transverse_speed_m_s: float | None = None, loss_factor: float | None = None, flexural_loss_factor: float | None = None, longitudinal_loss_factor: float | None = None, in_situ_loss_factor: float | None = None, thickness_critical_frequency_product_m_hz: float | None = None, borrowed: Mapping[str, str] = ..., ) ``` One row of a published materials table, with what the cell said. Every quantity is optional, because no two of the books this catalogue reads print the same columns: Hopkins gives a plate speed and no modulus, Mechel a modulus and no speed, Cremer both plus a shear modulus, Arau neither. A field is `None` when the page had nothing to put there, and `why_missing` says what it had instead. **The three longitudinal speeds are three fields**, and a fourth holds the one a page prints without saying which it is. They are three different waves and the books do not agree on what to call them. Cremer's `c_LII` and Bies' `sqrt(E/rho)` are the bar speed; Hopkins' quasi-longitudinal is the plate speed; and the bulk speed is neither. At `nu = 0.3` the plate speed is 4.8 per cent above the bar speed and the bulk speed is 16 per cent above it, which is the figure Cremer prints under his Eq. (3.32) with the warning that it matters which one is meant. One field holding whichever the page happened to print is the mistake this catalogue exists to prevent, so there is no field that means "whichever one the page happened to print". `longitudinal_speed_m_s` is not that: it means the page printed a longitudinal speed and said nothing about which, which is a statement about the source rather than a shrug about the wave. **The loss factors are four fields** for the same reason. A flexural loss factor is measured in bending and a longitudinal one is not; an in-situ one is not a property of the material at all, but of a panel installed in a building, support and radiation included; and a page that prints one without saying which it is has said something weaker than any of the three, which is what [`loss_factor`](/phonometry/reference/api/vibration/transfer-stiffness/#loss_factor) holds. The name, the citation, the variant and the hedges a cell can carry instead of a number (`basis`, `ranges`, `reported`, `unquantified`, `approximate`, `derived`, `converted`, `carried`, `attributed_to`) are the ones every catalogue row has; one is this catalogue's own and is described below. A cell the page marks as an estimate holds `"estimated"` in [`SolidMaterial.basis`](/phonometry/reference/api/solids/catalogue/#solidmaterial), and `row.basis_of(field) == "estimated"` is the question to ask before reading it as a measurement, which is the mistake this catalogue exists to prevent. **Attributes** | Name | Description | | :--- | :--- | | `density_kg_m3` | Density `rho`, in kg/m3. | | `youngs_modulus_pa` | Young's modulus `E`, in pascals. | | `shear_modulus_pa` | Shear modulus `G`, in pascals. | | `poisson_ratio` | Poisson's ratio `nu`. | | `longitudinal_speed_m_s` | A longitudinal speed for a page that prints one and does not say which of the three it is. Long's Table 12.1 does, with no modulus and no Poisson ratio beside it, so there is nothing on the page to settle it and nothing here that guesses. | | `bar_longitudinal_speed_m_s` | `sqrt(E/rho)`, the quasi-longitudinal speed on a rod, in m/s. | | `plate_longitudinal_speed_m_s` | `sqrt(E/(rho(1-nu^2)))`, the quasi-longitudinal speed on a plate, in m/s. | | `bulk_longitudinal_speed_m_s` | the pure longitudinal speed in an unbounded solid, in m/s. | | `transverse_speed_m_s` | `sqrt(G/rho)`, the shear wave speed, in m/s. | | `loss_factor` | Internal loss factor for a page that prints one and does not say which wave it was measured with. Mechel, Long and Arau all do. It is a separate field from the two below rather than a guess at which of them it is. | | `flexural_loss_factor` | Internal loss factor measured in bending. | | `longitudinal_loss_factor` | Internal loss factor measured with longitudinal waves. | | `in_situ_loss_factor` | Loss factor of a panel of this material as installed, which combines the internal, support and radiation losses and is therefore not a material constant. | | `thickness_critical_frequency_product_m_hz` | The `h.f_c` column, in m Hz, a property of the material alone and the cheapest cross-check there is between books that share no other column. | | `borrowed` | Field to the material it was taken from, for the cells a book fills from a similar material rather than leaving empty. A hedge like the shared ones: its keys name numeric fields of this class, and it is frozen when the row is built. | | `name` | The material as the table names it, attribution stripped. | | `variant` | Which specimen or condition this row is, when the page prints several under one name: `"chemically pure"`, `"direction x"`, `"0.68 mm diameter"`. Empty when the page prints one. | | `source` | Document, table, PDF page and printed folio. | | `table` | The data file this row was read from, without the extension, which is also the first half of its key in the catalogue that holds it. | | `basis` | What the source says a value is: a field name, or `"row"` for the whole row, to one of [`CATALOGUE_BASES`](/phonometry/reference/api/io/io/#catalogue_bases). Hopkins marks most of his Poisson ratios "Estimate", and those cells hold `"estimated"`; a datasheet that declares a class under a product standard would hold `"declared"`. A field with no entry takes the row's, and a row with neither is one whose source does not say, which is a different answer from any of the five. `basis_of` reads it. Independent of `derived`: this is what the source claims for a cell, that is what this library computed. | | `approximate` | Fields the page prints with a `~`. Not an estimate and not an interval: a number the author rounded on purpose. | | `derived` | Field to how it was computed, for the ones this library worked out from the cells the page did print. A derived value is never stored as if it had been read, and on every row the library builds it follows again from the row's own cells: `from_printed` writes it, and nothing else in the library does. One a caller passes to the literal constructor is the caller's word, which the row keeps and `printed_fields` leaves out with its value, as it leaves out every derived one. When the printed cells a value rests on do not all have one `basis`, the text names the basis of each, so a modulus worked out from a plate speed and a Poisson ratio Hopkins marks as an estimate says it rests on that estimate. A value converted from the unit the page prints is not derived (`converted` holds it), and neither is one the page gives by reference to another of its rows (`carried` does). | | `converted` | Field to `(figure, unit)`, the page's figure and the unit it is in, for a value this row holds in a unit the page does not use. Ver and Beranek print their damping materials in degrees Fahrenheit and pounds per square inch, and the row holds degrees Celsius and pascals, so `("3e5", "psi")` sits beside a modulus in pascals. The figure is kept as the page writes it, so the cell can always be read back in the page's own terms. The unit is the one the page prints with the figure or over its column. Long prints the figures of his musician bare, and the sabins recorded for them are a reading of the table, which is set in inches and pounds and names sabins on the next row; that row's note says so. A figure a packaged table prints with another SI prefix, such as the megapascals of Rossing Table 15.5, is held in the base unit with no entry here, and the table's `about` says so. | | `carried` | Field to where the page gives it from, for a value the page gives by reference to another of its rows rather than on this one: a cell left blank under a block whose first row prints the figure, as in Ver and Beranek Table 8.7, or a description that reads "Parecido al anterior" and prints no row number, as three rows of Harris Chapter 32 do, which refers to the row above it. The value is the page's, and this says which of its rows gives it. | | `ranges` | `(low, high)` for each field the page prints as an interval rather than a value. One end is `None` only for a bound whose open side the quantity has no limit on; the end the page prints is always a number, and a two-sided interval has two. | | `bounded_above` | The subset of `ranges` the page prints as `< x` or `<= x`, where the low end is a floor and not a measurement. | | `bounded_below` | The subset of `ranges` the page prints as `> x` or `>= x`, where the high end is the ceiling the quantity cannot pass and not a measurement: Cox gives an aerogel a porosity of `>0.75`, and the 1 beside it is what a porosity is, not what anybody measured. A quantity with no such ceiling leaves that end `None` rather than borrowing a number for it: ASHRAE prints `>45` for a duct wall whose radiated sound the background swamped, and a transmission loss has no value it cannot pass, so the open end is empty. It is never an infinity, which is not a number the page has and not a token JSON can carry. | | `reported` | Field to the values the page lists for it, for a cell that prints several with no single one: `"25, 207, 230"` or `"96, 200-450"`, readings from as many studies. Each entry is a number or a `(low, high)` pair. Not a range, because the page did not print one, and not variants, because the page does not say which is which. | | `unquantified` | Field to what the page printed in place of a number, for a cell that is neither empty nor numeric: `"Varies with frequency"`, `"model"`, `"…"` for a row of dots. What the page printed, and never a sentence about why the number is missing: `why_missing` composes that sentence around it, so a caller and a published table both get the cell as it reads on the page. | | `uncertainty` | Field to the plus-or-minus the page prints beside the value, in the same unit. Cox prints an effective flow resistivity of `(540 +/- 92) x 10^3`, and two of his rows print an uncertainty as large as the value itself. What the interval means is not stated on the page, so it is not stated here either: it is the number the page prints beside the value and nothing more. | | `misprinted` | Field to what the page prints there and why it cannot be that, for a cell whose defect is confirmed and registered in `docs/ERRATA.md`. The number is not served, because a catalogue that handed it over would put a value its own registry calls wrong behind every calculation downstream; it is not dropped either, because a reader reproducing the book needs to see what the book says. This is the narrowest of the hedges and the one that costs most to claim: a cell earns it only when the defect follows from the page itself or from something as settled as the molar mass of a named molecule, and never from one book disagreeing with another. | | `not_derivable` | Field to why this library leaves it empty although the arithmetic would reach it. Bies leaves the speed of his aluminium honeycomb panels blank, and the modulus and the density beside it are effective ones, so `sqrt(E/rho)` would put a one-dimensional speed on a panel that has none. A row says so here, and nothing fills the cell afterwards. | | `attributed_to` | Credit for a cell the book takes from someone else. Keyed by field name, or by `"row"` or `"table"` when the credit covers all of one. | | `group` | The heading of the block this row sits under, when the table prints its rows in named groups: Cox files each material under `"Fibrous materials"`, `"Cellular materials"`, `"Granular materials"` or `"Other"`. Empty for a table that prints one list. | | `note` | What the page says about this row beyond its numbers. | ### SolidMaterial.basis_of() ```python SolidMaterial.basis_of(field_name: str) -> str ``` What the source says this field is, one of [`CATALOGUE_BASES`](/phonometry/reference/api/io/io/#catalogue_bases). The five are `measured`, `declared`, `calculated`, `estimated` and `extended`. **Parameters** | Name | Description | | :--- | :--- | | `field_name` | One of the field names of this class. | **Returns:** The field's own entry in `basis`, else the row's, else the empty string, which means the source does not say. ### SolidMaterial.from_printed() *classmethod* ```python SolidMaterial.from_printed(**cells: Any) -> Self ``` A row built from the cells its page prints, completed and marked. The one path that works anything out. The cells are what the page prints, under the field names of the class and with the hedges each cell carries, as a data file writes them. A figure written under a unit the class takes as an alias of its own (an [`AbsorptionAreaSpectrum`](/phonometry/reference/api/materials/measured/#absorptionareaspectrum) takes `absorption_area_125_ft2` for `absorption_area_125_m2`) is converted on its digits with an exact factor and rounded once, and `converted` records the figure and its unit. The row is then built and held to the contract the class docstring lists, so every cell is checked before any arithmetic reads it. Last, the class fills what follows from those cells (a modulus from a plate speed, a density and a Poisson ratio), never over a cell that holds a value or one the row says something else about, and `derived` says how each filled value was reached and, when the cells it rests on do not share one `basis`, the basis of each. Cells the arithmetic cannot take are refused rather than turned into a value that would be wrong: a modulus of 1 GPa and a shear modulus of 0.1 GPa give a Poisson ratio of 4, which no isotropic solid has, and a row whose cells are not meant to give a value says so in `not_derivable`, which keeps the arithmetic from running. `Cls(...)` stays literal: it holds what it is given and works nothing out. To change a cell of a row and have what follows from it follow again, change it in `printed_fields` and build again here; `dataclasses.replace` would copy the derived values as they were: ```text cells = row.printed_fields() cells["density_kg_m3"] = 2400.0 row = type(row).from_printed(**cells) ``` **Parameters** | Name | Description | | :--- | :--- | | `cells` | The printed cells, as keywords of the class. | **Returns:** The row, with what follows from its cells filled in. **Raises** | Exception | When | | :--- | :--- | | CatalogueError | for a cell the contract refuses; for a `derived` among the cells, which is this method's to write; for a figure under a unit alias that is not a finite number, or that names a cell given under its own name or under another alias as well; and for printed cells a value that follows from them cannot be worked out of, naming the value and the cells. | | TypeError | for a name that is neither a field of the class nor a unit alias of one. | ### SolidMaterial.is_approximate() ```python SolidMaterial.is_approximate(field_name: str) -> bool ``` Whether the page prints this field with a `~`. **Parameters** | Name | Description | | :--- | :--- | | `field_name` | One of the numeric field names of this class. | **Returns:** `True` when the page rounded the cell on purpose. ### SolidMaterial.is_derived() ```python SolidMaterial.is_derived(field_name: str) -> bool ``` Whether this library computed this field instead of reading it. **Parameters** | Name | Description | | :--- | :--- | | `field_name` | One of the numeric field names of this class. | **Returns:** `True` when the page did not print it and the value follows from cells that it did. `derived` says how. A value the page prints in another unit, or gives by reference to another of its rows, answers `False`: the number is the page's, and `converted` or `carried` says so. ### SolidMaterial.printed() ```python SolidMaterial.printed( field_name: str, *, wanted_by: str = 'the caller', ) -> float ``` One quantity this page prints, or a refusal that says what it had. Every quantity of a row is optional, because the pages print different columns, so a caller passing one into a function that requires a float has to narrow it. Doing it here beats an assertion at each call site: the refusal names the field, who wanted it and what the page had in that cell, which is the difference between a cell the book left empty and a cell holding the word "model". **Parameters** | Name | Description | | :--- | :--- | | `field_name` | The quantity wanted. | | `wanted_by` | What wants it, named in the message. | **Returns:** The value, as a float. **Raises** | Exception | When | | :--- | :--- | | ValueError | when the page did not print a number there. | ### SolidMaterial.printed_fields() ```python SolidMaterial.printed_fields() -> dict[str, Any] ``` The cells the page prints, as `from_printed` takes them. Every field, the name, the citation, the table and every hedge included, except the values this library derived, `derived` itself, and a field left at a default that holds nothing (a quantity the page leaves out, an empty text or hedge). A text field whose default says something is kept even when it holds no text: the `per` of an area per unit is a person unless the row says otherwise, and a row that leaves it empty has said otherwise. A value converted from the page's unit and one the page gives by reference to another of its rows are the page's, so they stay, with `converted` and `carried` beside them. For every row `from_printed` builds, and so for every packaged one, `type(row).from_printed(**row.printed_fields())` is the row again, and changing a cell before building it again is how a row is edited without carrying a derived value that no longer follows from it. A `derived` passed to the literal constructor is the caller's own; it is left out here with its value, like every derived one, so building again gives back only what the class works out. **Returns:** A new dictionary of constructor keywords. The values are the ones the row holds, frozen as the row holds them. ### SolidMaterial.why_missing() ```python SolidMaterial.why_missing(field_name: str) -> str ``` Why this field is `None`, in the page's own terms. A catalogue that answers `None` and stops is asking the caller to guess whether the material has no such property, whether the book measured it and printed a dash, or whether the cell holds something that is not a number. Each of those is a different answer. **Parameters** | Name | Description | | :--- | :--- | | `field_name` | One of the numeric field names of this class. | **Returns:** What the page had in that cell, or the empty string when the field is not missing at all. A field the page has no column for and this library cannot derive, because the cells it would need are themselves a range, answers that it does not follow. **Raises** | Exception | When | | :--- | :--- | | AttributeError | for a name this class does not have, because a misspelt field would otherwise answer as if the cell were empty. | ## solids_named ```python solids_named(name: str) -> tuple[SolidMaterial, ...] ``` Every published row for a material, across the books. Comparing two books is the point of holding both, and it has to be a deliberate act: a lookup that returned one row for "steel" would be choosing between published values on the caller's behalf. **Parameters** | Name | Description | | :--- | :--- | | `name` | The material name as a table prints it, matched without regard to case: `"Steel"`, `"steel"`. | **Returns:** The rows whose [`SolidMaterial.name`](/phonometry/reference/api/solids/catalogue/#solidmaterial) matches, in the order the tables are read, which is empty when no page names it.