PhysicalParticles.jl

Physical vector and particle types for Julia
Author JuliaAstroSim
Popularity
2 Stars
Updated Last
2 Years Ago
Started In
November 2019

PhysicalParticles.jl

codecov

Physical particle types for scientific simulation. Manipulate vectors as simple as numbers!

Installation

]add PhysicalParticles

or

using Pkg; Pkg.add("PhysicalParticles")

or

using Pkg; Pkg.add("https://github.com/JuliaAstroSim/PhysicalParticles.jl")

To test the Package:

]test PhysicalParticles

Documentation

  • Devdocumentation of the in-development version.

Basic Usage

Vectors

julia> using PhysicalParticles, Unitful, UnitfulAstro

julia> a = PVector()
PVector{Float64}(0.0, 0.0, 0.0)

julia> b = PVector(1.0u"m", 2.0u"m", 3.0u"m")
PVector(1.0 m, 2.0 m, 3.0 m)

julia> c = PVector2D(u"m/s")
PVector2D(0.0 m s^-1, 0.0 m s^-1)

julia> uconvert(u"m", PVector(1.0, 1.0, 1.0, u"km"))
PVector(1000.0 m, 1000.0 m, 1000.0 m)

julia> PVector(BigFloat)
PVector{BigFloat}(0.0, 0.0, 0.0)

julia> PVector2D(BigInt, u"m")
PVector2D(0 m, 0 m)


julia> PVector(1.0, 1.0) * im
PVector2D{Complex{Float64}}(0.0 + 1.0im, 0.0 + 1.0im)

julia> b * 2.0u"s"
PVector(2.0 m s, 4.0 m s, 6.0 m s)

julia> b + PVector(2.0, 2.0, 2.0, u"m") / 2
PVector(2.0 m, 3.0 m, 4.0 m)

julia> norm(PVector2D(3.0f0,4.0f0))
5.0f0

julia> normalize(PVector(3.0, 4.0))
PVector2D{Float64}(0.6, 0.8)

julia> d = PVector(3u"kpc", 4u"kpc")
PVector2D(3 kpc, 4 kpc)

julia> norm(d)
1.5428387907456837e20 m



julia> distance(PVector2D(0.0, 0.0), PVector2D(3.0, 4.0))
5.0

julia> rotate(PVector(1.0, 0.0), 0.5pi)
PVector2D{Float64}(6.123233995736766e-17, 1.0)

julia> rotate(PVector(1.0, 0.0, 0.0), 0.0, 0.0, 0.5pi)
PVector{Float64}(6.123233995736766e-17, 1.0, 0.0)

julia> rotate_z(PVector(1.0, 0.0, 0.0), 90.0u"°")
PVector{Float64}(0.0, 1.0, 0.0)

julia> rotate(PVector(1.0, 0.0, 0.0), 0.0, 0.0, 90.0u"°", PVector(-1.0, 0.0, 0.0))
PVector{Float64}(-1.0, 2.0, 0.0)

julia> rotate(PVector(0.0, 1.0, 0.0), PVector(0.0, 1.0, 1.0), pi)
PVector{Float64}(-8.659560562354932e-17, -2.220446049250313e-16, 0.9999999999999998)

# Coordinate Transformations
julia> cylinderial(PVector(sqrt(2), sqrt(2), 1.0, u"m"))
(2.0 m, 0.7853981633974484, 1.0 m)

julia> cylinderial2xyz(2.0u"m", pi/4, 1.0u"m")
PVector(1.4142135623730951 m, 1.414213562373095 m, 1.0 m)

julia> spherical(PVector(sqrt(0.5), sqrt(0.5), 1.0, u"m"))
(1.4142135623730951 m, 0.7853981633974484, 0.7853981633974483)

julia> spherical2xyz(sqrt(2)u"m", pi/4, pi/4)
PVector(0.7071067811865476 m, 0.7071067811865475 m, 1.0000000000000002 m)

julia> zero(PVector{Float64})
PVector{Float64}(0.0, 0.0, 0.0)

julia> iszero(PVector(u"m"))
true

julia> isnan(PVector(NaN, NaN))
true

julia> PVector2D(1.0, 1.0)  PVector2D(1.0 + 1.0e-8, 1.0 + 1.0e-8)
true


julia> ustrip(PVector(1.0, 1.0, 1.0, u"km"))
PVector{Float64}(1.0, 1.0, 1.0)

julia> ustrip(u"m", PVector(1.0, 1.0, 1.0, u"km"))
PVector{Float64}(1000.0, 1000.0, 1000.0)

Particles

We provide 2D version for each type below, for example, the 2D version of Ball is Ball2D:

julia> Massless()
Massless 0: Pos = PVector{Float64}(0.0, 0.0, 0.0), Vel = PVector{Float64}(0.0, 0.0, 0.0)

julia> Massless(PVector(0.0, 0.0, 0.0), PVector(), 1)
Massless 1: Pos = PVector{Float64}(0.0, 0.0, 0.0), Vel = PVector{Float64}(0.0, 0.0, 0.0)

julia> Massless2D(uCGS)
Massless 0: Pos = PVector2D(0.0 cm, 0.0 cm), Vel = PVector2D(0.0 cm s^-1, 0.0 cm s^-1)

julia> Ball()
Ball 0: Pos = PVector{Float64}(0.0, 0.0, 0.0), Vel = PVector{Float64}(0.0, 0.0, 0.0), Acc = PVector{Float64}(0.0, 0.0, 0.0), Mass = 0.0

julia> Ball(PVector(0.0u"m", 0.0u"m", 0.0u"m"), PVector(u"m/s"), PVector(u"m/s^2"), 0.0u"kg", 1)
Ball 1: Pos = PVector(0.0 m, 0.0 m, 0.0 m), Vel = PVector(0.0 m s^-1, 0.0 m s^-1, 0.0 m s^-1), Acc = PVector(0.0 m s^-2, 0.0 m s^-2, 0.0 m s^-2), Mass = 0.0 kg

julia> Star()
Star 0 STAR: Pos = PVector{Float64}(0.0, 0.0, 0.0), Vel = PVector{Float64}(0.0, 0.0, 0.0), Acc = PVector{Float64}(0.0, 0.0, 0.0), Mass = 0.0, Ti_endstep = 0, Ti_begstep = 0, Potential = 0.0, OldAcc = 0.0

julia> SPHGas()
SPHGas 0 GAS: Pos = PVector{Float64}(0.0, 0.0, 0.0), Vel = PVector{Float64}(0.0, 0.0, 0.0), Acc = PVector{Float64}(0.0, 0.0, 0.0), Mass = 0.0, Ti_endstep = 0, Ti_begstep = 0, Potential = 0.0, OldAcc = 0.0, Entropy = 0.0, Density = 0.0, Hsml = 0.0, Left = 0.0, Right = 0.0, NumNgbFound = 0, RotVel = PVector{Float64}(0.0, 0.0, 0.0), DivVel = 0.0, CurlVel = 0.0, dHsmlRho = 0.0, Pressure = 0.0, DtEntropy = 0.0, MaxSignalVel = 0.0

julia> a = Star(uAstro)
Star 0 STAR: Pos = PVector(0.0 kpc, 0.0 kpc, 0.0 kpc), Vel = PVector(0.0 kpc Gyr^-1, 0.0 kpc Gyr^-1, 0.0 kpc Gyr^-1), Acc = PVector(0.0 kpc Gyr^-2, 0.0 kpc Gyr^-2, 0.0 kpc Gyr^-2), Mass = 0.0 M⊙, Ti_endstep = 0, Ti_begstep = 0, Potential = 0.0 kpc^2 M⊙ Gyr^-2, OldAcc = 0.0 kpc Gyr^-2

julia> b = SPHGas(uAstro)
SPHGas 0 GAS: Pos = PVector(0.0 kpc, 0.0 kpc, 0.0 kpc), Vel = PVector(0.0 kpc Gyr^-1, 0.0 kpc Gyr^-1, 0.0 kpc Gyr^-1), Acc = PVector(0.0 kpc Gyr^-2, 0.0 kpc Gyr^-2, 0.0 kpc Gyr^-2), Mass = 0.0 M⊙, Ti_endstep = 0, Ti_begstep = 0, Potential = 0.0 kpc^2 M⊙ Gyr^-2, OldAcc = 0.0 kpc Gyr^-2, Entropy = 0.0 kpc^2 M⊙ Gyr^-2 K^-1, Density = 0.0 M⊙ kpc^-3, Hsml = 0.0 kpc, Left = 0.0, Right = 0.0, NumNgbFound = 0, RotVel = PVector(0.0 kpc Gyr^-1, 0.0 kpc Gyr^-1, 0.0 kpc Gyr^-1), DivVel = 0.0 Gyr^-1, CurlVel = 0.0 Gyr^-1, dHsmlRho = 0.0 kpc, Pressure = 0.0 M⊙ Gyr^-2 kpc^-1, DtEntropy = 0.0 kpc^2 M⊙ Gyr^-3 K^-1, MaxSignalVel = 0.0 kpc Gyr^-1

julia> distance(a,b)
0.0 m

StructArrays.jl support

StructArray provides a more efficient way to iterate on a field of particles:

sArray = [Star() for i in 1:5]
sStruct = StructArray(sArray)

# Easier to set properties, and even faster!
sStruct.Mass[1] = 1000.0

assign_particles(sStruct, :Pos, randn_pvector(5))

mean(sStruct.Pos)

Random and Conversion

julia> p = rand_pvector(3)
3-element Array{PVector{Float64},1}:
 PVector{Float64}(0.899541890819791, 0.49609709458549345, 0.22817220536717397)
 PVector{Float64}(0.21907343513386301, 0.39110699072427035, 0.3502946880565312)
 PVector{Float64}(0.8107782153679699, 0.20218167820102884, 0.94236923352867)

julia> pu = rand_pvector(3, u"m")
3-element Array{PVector{Quantity{Float64,𝐋,Unitful.FreeUnits{(m,),𝐋,nothing}}},1}:
 PVector(0.5346672699901402 m, 0.6988269071898365 m, 0.8120077168096169 m)  
 PVector(0.46886820909936744 m, 0.9575982422487646 m, 0.10413358701332642 m)
 PVector(0.0219005354136228 m, 0.327612194392396 m, 0.2837471711064179 m)

julia> p_Ball = [Ball(uSI) for i=1:3]
3-element Array{Ball{Int64},1}:
 Ball 0: Pos = PVector(0.0 m, 0.0 m, 0.0 m), Vel = PVector(0.0 m s^-1, 0.0 m s^-1, 0.0 m s^-1), Acc = PVector(0.0 m s^-2, 0.0 m s^-2, 0.0 m s^-2), Mass = 0.0 kg
 Ball 0: Pos = PVector(0.0 m, 0.0 m, 0.0 m), Vel = PVector(0.0 m s^-1, 0.0 m s^-1, 0.0 m s^-1), Acc = PVector(0.0 m s^-2, 0.0 m s^-2, 0.0 m s^-2), Mass = 0.0 kg
 Ball 0: Pos = PVector(0.0 m, 0.0 m, 0.0 m), Vel = PVector(0.0 m s^-1, 0.0 m s^-1, 0.0 m s^-1), Acc = PVector(0.0 m s^-2, 0.0 m s^-2, 0.0 m s^-2), Mass = 0.0 kg

julia> assign_points(p_Ball, :Pos, pu)

julia> p_Ball
3-element Array{Ball{Int64},1}:
 Ball 0: Pos = PVector(0.5346672699901402 m, 0.6988269071898365 m, 0.8120077168096169 m), Vel = PVector(0.0 m s^-1, 0.0 m s^-1, 0.0 m s^-1), Acc = PVector(0.0 m s^-2, 0.0 m s^-2, 0.0 m s^-2), Mass = 0.0 kg
 Ball 0: Pos = PVector(0.46886820909936744 m, 0.9575982422487646 m, 0.10413358701332642 m), Vel = PVector(0.0 m s^-1, 0.0 m 
s^-1, 0.0 m s^-1), Acc = PVector(0.0 m s^-2, 0.0 m s^-2, 0.0 m s^-2), Mass = 0.0 kg
 Ball 0: Pos = PVector(0.0219005354136228 m, 0.327612194392396 m, 0.2837471711064179 m), Vel = PVector(0.0 m s^-1, 0.0 m s^-1, 0.0 m s^-1), Acc = PVector(0.0 m s^-2, 0.0 m s^-2, 0.0 m s^-2), Mass = 0.0 kg


julia> pconvert([1.0, 2.0, 3.0])
PVector{Float64}(1.0, 2.0, 3.0)

julia> pconvert([1.0u"m" 4.0u"m";
                 2.0u"m" 5.0u"m";
                 3.0u"m" 6.0u"m"])
2-element Array{PVector,1}:
 PVector(1.0 m, 2.0 m, 3.0 m)
 PVector(4.0 m, 5.0 m, 6.0 m)

Extent

julia> p = [Ball(PVector(-1.0u"m", 1.0u"m", 1.0u"m"), PVector(u"m/s"), PVector(u"m/s^2"), 1.0u"kg", 1),
            Ball(PVector(3.0u"m", -3.0u"m", -3.0u"m"), PVector(u"m/s"), PVector(u"m/s^2"), 3000.0u"g", 2)]
2-element Array{Ball{Int64},1}:
 Ball 1: Pos = PVector(-1.0 m, 1.0 m, 1.0 m), Vel = PVector(0.0 m s^-1, 0.0 m s^-1, 0.0 m s^-1), Acc = PVector(0.0 m s^-2, 0.0 m s^-2, 0.0 m s^-2), Mass = 1.0 kg
 Ball 2: Pos = PVector(3.0 m, -3.0 m, -3.0 m), Vel = PVector(0.0 m s^-1, 0.0 m s^-1, 0.0 m s^-1), Acc = PVector(0.0 m s^-2, 0.0 m s^-2, 0.0 m s^-2), Mass = 1000.0 g

julia> minimum_x(p)
-1.0 m

julia> maximum_x(p)
3.0 m

julia> center(p)
PVector(1.0 m, -1.0 m, -1.0 m)

julia> pos_center(p)
PVector(1.0 m, -1.0 m, -1.0 m)

julia> mass_center(p)
PVector(2.0 m, -2.0 m, -2.0 m)

julia> median(p, :Pos)
PVector(1.0 m, -1.0 m, -1.0 m)

julia> extent(p)
Extent: xMin = -1.0 m, xMax = 3.0 m, yMin = -3.0 m, yMax = 1.0 m, zMin = -3.0 m, zMax = 1.0 m, SideLength = 4.0 m, Center = PVector(1.0 m, -1.0 m, -1.0 m)

There are differences among center, pos_center, mass_center and median:

  • center: box center of particles
  • pos_center: average position of particles
  • mass_center: mass weighted average position of particles
  • median: middle value of positions of particles

Units

Units are supported by Unitful.jl and UnitfulAstro.jl

Set default units by

const uSI = u"m,s,A,K,cd,kg,mol"
preferunits(uSI)

or simply call si(). astro() and cgs() are implemented in the same way.

This would affect unit promotions in Unitful package and default outputs in related packages, by setting Unitful.promotion and PhysicalParticles.uDefaults respectively.

Interfaces to get basic units:

julia> getunits()
(m, s, A, K, cd, kg, mol)

julia> getunits(uAstro)
(kpc, Gyr, A, K, cd, M⊙, mol)

julia> getunits(nothing)
(nothing, nothing, nothing, nothing, nothing, nothing, nothing)

julia> getuLength()
m

julia> getuTime(uSI)
s

julia> getuCurrent(uCGS)
A

julia> getuTemperature(nothing)

julia> getuLuminosity()
cd

julia> getuMass()
kg

julia> getuAmount()
mol

axisunit provides a convenient way to print units in the axis of plots:

julia> axisunit(nothing)
""

julia> axisunit(u"m")
" [m]"

julia> axisunit("Time", u"Gyr")
"TIme [Gyr]"

Constants

Physical constants are imported from CODATA2018 supported by PhysicalConstants.jl. However, constants in PhysicalConstants may cause type error if they are not converted to default units.

To prevent this problem, construct an immutable struct Constant corresponding to the provided units:

julia> Constant()
Converted Constants:
    G = 4.498502151469553e-6 kpc^3 M⊙^-1 Gyr^-2
    m_e = 4.581240435253955e-61 M⊙
    m_n = 8.423451938769546e-58 M⊙
    m_p = 8.411856872862986e-58 M⊙
    k_B = 7.2624677363918e-60 kpc^2 M⊙ K^-1 Gyr^-2
    ACC0 = 3872.920970357523 kpc Gyr^-2

julia> Constant(uSI)
Converted Constants:
    G = 6.6743e-11 m^3 kg^-1 s^-2
    m_e = 9.1093837015e-31 kg
    m_n = 1.67492749804e-27 kg
    m_p = 1.67262192369e-27 kg
    k_B = 1.380649e-23 kg m^2 K^-1 s^-2
    ACC0 = 1.2e-10 m s^-2

julia> Constant(uCGS)
Converted Constants:
    G = 6.674299999999999e-8 cm^3 g^-1 s^-2
    m_e = 9.1093837015e-28 g
    m_n = 1.67492749804e-24 g
    m_p = 1.67262192369e-24 g
    k_B = 1.380649e-16 g cm^2 K^-1 s^-2
    ACC0 = 1.2e-8 cm s^-2

julia> using Unitful

julia> ustrip(Constant())
Converted Constants:
    G = 4.498502151469553e-6
    m_e = 4.581240435253955e-61
    m_n = 8.423451938769546e-58
    m_p = 8.411856872862986e-58
    k_B = 7.2624677363918e-60
    ACC0 = 3872.920970357523

Zerovalues

ZeroValue is useful for accumulated summation, array initialization, etc. Examples:

ZeroValue(nothing)
ZeroValue()
ZeroValue(uSI)
ZeroValue(uCGS)

References

Package ecosystem

Used By Packages