Resources Numerical accuracy
Calculations
Every calculation under our calculation policies: what it works out, its formula and the precision it runs at. Open one to see its code as it is in the released app.
Calculations
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Permeability of free space
The constant μ0 used in every hand formula.
μ0 = 4 × 10⁻⁷ × π
Magnetics add-on: template shapes and hand formulas addons/magnetics/lib/templates.js64-bit- PartCraft
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Round conductor as a polygon
The corners of the polygon that stands for a round wire.
pᵢ = (cx + r cos(2πi ÷ n), cy + r sin(2πi ÷ n)), n = 48
Magnetics add-on: template shapes and hand formulas addons/magnetics/lib/templates.js64-bit- PartCraft
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C-core gap field
The flux density in the air gap of a C-core electromagnet by the magnetic circuit formula.
B = μ0 × NI ÷ ((g + l ÷ μr) × 10⁻³), l = 2(w − tk) + 2(h − tk) − g
Magnetics add-on: template shapes and hand formulas addons/magnetics/lib/templates.js64-bit- PartCraft
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Magnet in a closed iron frame
The flux density in a permanent magnet set in one leg of a closed frame.
B = Br × (lm ÷ μrm) ÷ (lm ÷ μrm + L ÷ μr), L = 2(w − tk) + 2(h − tk) − lm
Magnetics add-on: template shapes and hand formulas addons/magnetics/lib/templates.js64-bit- PartCraft
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Field round one wire
The flux density at two radii from the center of a round conductor.
B = μ0 × I ÷ (2π × r × 10⁻³), r = 2a
Magnetics add-on: template shapes and hand formulas addons/magnetics/lib/templates.js64-bit- PartCraft
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Force between two wires
The force per meter between two parallel conductors.
F = μ0 × |I₁ × I₂| ÷ (2π × d × 10⁻³)
Magnetics add-on: template shapes and hand formulas addons/magnetics/lib/templates.js64-bit- PartCraft
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Template sizes within their ranges
Clamps each size a person types to the template's allowed range.
Magnetics add-on: template shapes and hand formulas addons/magnetics/lib/templates.js64-bit- PartCraft
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Frame of the study's plane
The origin and axes of the plane the result is drawn in.
x = (helper × n) ÷ |helper × n|; y = n × x
Magnetics add-on: the result drawn as display bodies addons/magnetics/lib/bodies.js32-bit, display only- PartCraft
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Triangle cut to the crop rectangle
Cuts a field triangle to the rectangle that is shown.
Magnetics add-on: the result drawn as display bodies addons/magnetics/lib/bodies.js32-bit, display only- PartCraft
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Field color bands
The color band each triangle falls in.
band = min(9, floor(|B| ÷ top × 10))
Magnetics add-on: the result drawn as display bodies addons/magnetics/lib/bodies.js32-bit, display only- PartCraft
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Defining constants
The pound, standard gravity, inch and foot, and the pound-force, gallon and British thermal unit built from them.
lbf = 0.45359237 × 9.80665; gal = 231 × 0.0254³; BTU = 1055.05585262 J
Engineering units: factors, dimensions and conversion engineer/eng-units.jsExact- PartCraft
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Unit table
Each unit's factor to SI and its dimension.
Engineering units: factors, dimensions and conversion engineer/eng-units.jsExact- PartCraft
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SI prefixes
A prefixed unit such as kPa or mm from its base unit.
factor = prefix × unit factor
Engineering units: factors, dimensions and conversion engineer/eng-units.js64-bit- PartCraft
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Combining units
The factor and dimension of a product or quotient of two units.
f = f_a × f_bᵉ; dimension = d_a + e × d_b
Engineering units: factors, dimensions and conversion engineer/eng-units.js64-bit- PartCraft
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Reading a unit text
Turns a text such as W/(m^2 K) into one factor and one dimension.
Engineering units: factors, dimensions and conversion engineer/eng-units.js64-bit- PartCraft
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Value to SI
A value in a given unit as its SI value.
SI = v × f
Engineering units: factors, dimensions and conversion engineer/eng-units.js64-bit- PartCraft
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Value from SI
An SI value in a given unit.
v = SI ÷ f
Engineering units: factors, dimensions and conversion engineer/eng-units.js64-bit- PartCraft
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Unit to unit
A value converted from one unit to another of the same kind.
result = v × f_from ÷ f_to
Engineering units: factors, dimensions and conversion engineer/eng-units.js64-bit- PartCraft
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Temperature points
Celsius and Fahrenheit readings to and from kelvin.
K = °C + 273.15; K = (°F − 32) × 5 ÷ 9 + 273.15
Engineering units: factors, dimensions and conversion engineer/eng-units.js64-bit- PartCraft
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Power and logarithm used
Which power and logarithm functions the curves are evaluated with.
Material packs: property curves by temperature engineer/material-pack.js64-bit- PartCraft
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One curve segment
The fitted curve's value at a temperature.
y = 10^(Σ cᵢ Lⁱ), L = log10 T; or y = c₀ + T(c₁ + T(c₂ + T(c₃ + T c₄)))
Material packs: property curves by temperature engineer/material-pack.js64-bit- PartCraft
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Property at a temperature
The property value with its unit, range, fit error and source.
value = curve(T) × scale
Material packs: property curves by temperature engineer/material-pack.js64-bit- PartCraft
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Series coefficients
The factors 1/n! of the sine and cosine series.
cₙ = ±1 ÷ n!
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Angle reduction
Brings an angle into [−π, π].
n = floor(x ÷ 2π + ½); r = (x − n × 2π_hi) − n × 2π_lo
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Sine series
The sine of a reduced angle.
sin r = r(c₀ + c₁r² + … + c₁₂r²⁴)
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Cosine series
The cosine of a reduced angle.
cos r = c₀ + c₁r² + … + c₁₂r²⁴
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Sine
sin x for any finite x.
sin r = sin(π − r) for r > π/2; sin r = sin(−π − r) for r < −π/2
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Cosine
cos x for any finite x.
cos r = −cos(π − |r|) for |r| > π/2
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Exponential
The exponential eˣ of a number.
k = floor(x ÷ ln 2 + ½); r = (x − k × ln2_hi) − k × ln2_lo; eˣ = 2ᵏ × Σ rⁿ ÷ n! (n = 0 … 18)
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Natural logarithm
The natural logarithm ln x of a number.
x = m × 2ᵉ, m in [√2/2, √2]; ln m = 2(s + s³/3 + … + s²⁹/29), s = (m − 1) ÷ (m + 1); ln x = e × ln2_hi + (ln m + e × ln2_lo)
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Base-2 logarithm
The base-2 logarithm log₂ x of a number.
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Base-10 logarithm
The base-10 logarithm log₁₀ x of a number.
log₁₀ x = ln x ÷ 2.302585092994046
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Whole-number power
xⁿ for a whole n ≥ 0.
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Power
A number x raised to a power y.
xʸ = exp(y × ln x) for a fractional y
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Arctangent
The arctangent atan x of a number.
atan z = 2·atan(z ÷ (1 + √(1 + z²))), twice; then 4(z − z³/3 + … + z⁴¹/41)
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Two-argument arctangent
The angle of the point (x, y).
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Arcsine
The arcsine asin x of a number in [−1, 1].
asin x = atan2(x, √((1 − x)(1 + x)))
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Arccosine
The arccosine acos x of a number in [−1, 1].
acos x = 2·atan2(√(1 − x), √(1 + x))
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Tangent
The tangent tan x of an angle.
tan x = sin x ÷ cos x
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Hyperbolic sine
The hyperbolic sine sinh x of a number.
sinh x = (eˣ − e⁻ˣ) ÷ 2
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Hyperbolic cosine
The hyperbolic cosine cosh x of a number.
cosh x = (eˣ + 1 ÷ eˣ) ÷ 2
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Hyperbolic tangent
The hyperbolic tangent tanh x of a number.
tanh x = (e²ˣ − 1) ÷ (e²ˣ + 1)
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Cube root
The cube root ∛x of a number.
r₀ = exp(ln|x| ÷ 3); r ← r − (r³ − |x|) ÷ (3r²), twice
Deterministic sine, cosine, exp, log and power field/detmath.js64-bit- PartCraft
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Sphere
Signed distance to a sphere.
d = √((x − cx)² + (y − cy)² + (z − cz)²) − r
Field shapes: signed distance functions field/field.js64-bit- PartCraft
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Box with rounded edges
Signed distance to a box, optionally with rounded edges and corners.
q = |p − c| − (half − round); d = |max(q, 0)| + min(max(q_x, q_y, q_z), 0) − round
Field shapes: signed distance functions field/field.js64-bit- PartCraft
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Cylinder
Signed distance to a cylinder between two points.
t = (p − m)·u; d_r = |p − m − t·u| − r; d_t = |t| − L ÷ 2; d = |max(d_r, d_t, 0)| + min(max(d_r, d_t), 0)
Field shapes: signed distance functions field/field.js64-bit- PartCraft
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Torus
Signed distance to a torus about the z axis.
d = √((√(x² + y²) − R)² + z²) − r
Field shapes: signed distance functions field/field.js64-bit- PartCraft
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Half space
Signed distance to a plane.
d = (n·p − d₀) ÷ |n|
Field shapes: signed distance functions field/field.js64-bit- PartCraft
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Solid of revolution
Signed distance to the solid under a profile r(x) turned about the x axis.
ρ = √(y² + z²); d = least distance from (x, ρ) to the profile's segments; inside when ρ ≤ r(x)
Field shapes: signed distance functions field/field.js64-bit- PartCraft
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Union, intersection and subtraction
Combines shapes by union, intersection or subtraction.
union = min(a, b); intersection = max(a, b); subtraction = max(a, −b)
Field shapes: signed distance functions field/field.js64-bit- PartCraft
A calculation is added only after its source was read. Each statement can be checked in the code shown on its policy's page; the app repositories are public. When a release changes a calculation, its page says so until it has been read again.