2. Particles: Load Selected Variables and Data Ranges
Simulation Overview
using Mera
info = getinfo(300, "../../testing/simulations/mw_L10");[Mera]: 2023-04-10T11:09:58.577
Code: RAMSES
output [300] summary:
mtime: 2023-04-09T05:34:09
ctime: 2023-04-10T08:08:14.488
=======================================================
simulation time: 445.89 [Myr]
boxlen: 48.0 [kpc]
ncpu: 640
ndim: 3
-------------------------------------------------------
amr: true
level(s): 6 - 10 --> cellsize(s): 750.0 [pc] - 46.88 [pc]
-------------------------------------------------------
hydro: true
hydro-variables: 7 --> (:rho, :vx, :vy, :vz, :p, :var6, :var7)
hydro-descriptor: (:density, :velocity_x, :velocity_y, :velocity_z, :pressure, :scalar_00, :scalar_01)
γ: 1.6667
-------------------------------------------------------
gravity: true
gravity-variables: (:epot, :ax, :ay, :az)
-------------------------------------------------------
particles: true
- Nstars: 5.445150e+05
particle-variables: 7 --> (:vx, :vy, :vz, :mass, :family, :tag, :birth)
particle-descriptor: (:position_x, :position_y, :position_z, :velocity_x, :velocity_y, :velocity_z, :mass, :identity, :levelp, :family, :tag, :birth_time)
-------------------------------------------------------
rt: false
clumps: false
-------------------------------------------------------
namelist-file: ("&COOLING_PARAMS", "&SF_PARAMS", "&AMR_PARAMS", "&BOUNDARY_PARAMS", "&OUTPUT_PARAMS", "&POISSON_PARAMS", "&RUN_PARAMS", "&FEEDBACK_PARAMS", "&HYDRO_PARAMS", "&INIT_PARAMS", "&REFINE_PARAMS")
-------------------------------------------------------
timer-file: true
compilation-file: false
makefile: true
patchfile: true
=======================================================Select Variables
Choose from the existing particle variables listed in the simulation-info. The functions in Mera "know" the predefined particle variable names:
- From >= ramses-version-2018: :vx, :vy, :vz, :mass, :family, :tag, :birth, :metals :var9,....
- For =< ramses-version-2017: :vx, :vy, :vz, :mass, :birth, :var6, :var7,....
- Currently, the following variables are loaded by default (if exist): :level, :x, :y, :z, :id, :family, :tag.
- The cpu number associated with the particles can be loaded with the variable names: :cpu or :varn1
- In a future version the variable names from the particle descriptor can be used by setting the field info.descriptor.useparticles = true .
Read all variables by default
particles = getparticles(info);[Mera]: Get particle data: 2023-04-10T11:10:06.672
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(1, 2, 3, 4, 7) = (:vx, :vy, :vz, :mass, :birth)
domain:
xmin::xmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
ymin::ymax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
zmin::zmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
Found 5.445150e+05 particles
Memory used for data table :38.42913246154785 MB
-------------------------------------------------------particles.dataTable with 544515 rows, 12 columns:
Columns:
# colname type
────────────────────
1 level Int32
2 x Float64
3 y Float64
4 z Float64
5 id Int32
6 family Int8
7 tag Int8
8 vx Float64
9 vy Float64
10 vz Float64
11 mass Float64
12 birth Float64Select several variables w/o a keyword
particles_a = getparticles(info, vars=[:mass, :birth]); [Mera]: Get particle data: 2023-04-10T11:10:09.828
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(4, 7) = (:mass, :birth)
domain:
xmin::xmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
ymin::ymax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
zmin::zmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
Found 5.445150e+05 particles
Memory used for data table :25.96580410003662 MB
-------------------------------------------------------The same variables can be read by using the var-number:
particles_a = getparticles(info, vars=[:var4, :var7]); [Mera]: Get particle data: 2023-04-10T11:10:15.319
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(4, 7) = (:mass, :birth)
domain:
xmin::xmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
ymin::ymax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
zmin::zmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
Found 5.445150e+05 particles
Memory used for data table :25.96580410003662 MB
-------------------------------------------------------A keyword argument for the variables is not needed if the following order is preserved: InfoType-object, variables:
particles_a = getparticles(info, [:mass, :birth]); [Mera]: Get particle data: 2023-04-10T11:10:17.681
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(4, 7) = (:mass, :birth)
domain:
xmin::xmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
ymin::ymax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
zmin::zmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
Found 5.445150e+05 particles
Memory used for data table :25.96580410003662 MB
-------------------------------------------------------particles_a.dataTable with 544515 rows, 9 columns:
level x y z id family tag mass birth
──────────────────────────────────────────────────────────────────────────
9 9.17918 22.4404 24.0107 128710 2 0 8.00221e-7 8.86726
9 9.23642 21.5559 24.0144 126838 2 0 8.00221e-7 8.71495
9 9.35638 20.7472 24.0475 114721 2 0 8.00221e-7 7.91459
9 9.39529 21.1854 24.0155 113513 2 0 8.00221e-7 7.85302
9 9.42686 20.9697 24.0162 120213 2 0 8.00221e-7 8.2184
9 9.42691 22.2181 24.0137 125689 2 0 8.00221e-7 8.6199
9 9.48834 22.0913 24.0137 126716 2 0 8.00221e-7 8.70493
9 9.5262 20.652 24.0179 115550 2 0 8.00221e-7 7.96008
9 9.60376 21.2814 24.0155 116996 2 0 8.00221e-7 8.03346
9 9.6162 20.6243 24.0506 125003 2 0 8.00221e-7 8.56482
9 9.62155 20.6248 24.0173 112096 2 0 8.00221e-7 7.78062
9 9.62252 24.4396 24.0206 136641 2 0 8.00221e-7 9.44825
⋮
10 37.7913 25.6793 24.018 141792 2 0 8.00221e-7 9.78881
10 37.8255 22.6271 24.0279 143663 2 0 8.00221e-7 9.89052
10 37.8451 22.7506 24.027 138989 2 0 8.00221e-7 9.61716
10 37.8799 25.5668 24.0193 150226 2 0 8.00221e-7 10.2294
10 37.969 23.2135 24.0273 142995 2 0 8.00221e-7 9.85439
10 37.9754 22.6288 24.0265 137301 2 0 8.00221e-7 9.4959
10 37.9811 23.2854 24.0283 145294 2 0 8.00221e-7 9.9782
10 37.9919 22.873 24.0271 132010 2 0 8.00221e-7 9.12003
10 37.9966 23.092 24.0281 136766 2 0 8.00221e-7 9.45574
10 38.0328 22.8404 24.0265 141557 2 0 8.00221e-7 9.77493
10 38.0953 22.8757 24.0231 133214 2 0 8.00221e-7 9.20251Select one variable
In this case, no array and keyword is necessary, but preserve the following order: InfoType-object, variable:
particles_c = getparticles(info, :vx ); [Mera]: Get particle data: 2023-04-10T11:10:22.160
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(1,) = (:vx,)
domain:
xmin::xmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
ymin::ymax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
zmin::zmax: 0.0 :: 1.0 ==> 0.0 [kpc] :: 48.0 [kpc]
Found 5.445150e+05 particles
Memory used for data table :21.81136131286621 MB
-------------------------------------------------------particles_c.dataTable with 544515 rows, 8 columns:
level x y z id family tag vx
─────────────────────────────────────────────────────────────────
9 9.17918 22.4404 24.0107 128710 2 0 0.670852
9 9.23642 21.5559 24.0144 126838 2 0 0.810008
9 9.35638 20.7472 24.0475 114721 2 0 0.93776
9 9.39529 21.1854 24.0155 113513 2 0 0.870351
9 9.42686 20.9697 24.0162 120213 2 0 0.899373
9 9.42691 22.2181 24.0137 125689 2 0 0.717235
9 9.48834 22.0913 24.0137 126716 2 0 0.739564
9 9.5262 20.652 24.0179 115550 2 0 0.946747
9 9.60376 21.2814 24.0155 116996 2 0 0.893236
9 9.6162 20.6243 24.0506 125003 2 0 0.996445
9 9.62155 20.6248 24.0173 112096 2 0 0.960817
9 9.62252 24.4396 24.0206 136641 2 0 0.239579
⋮
10 37.7913 25.6793 24.018 141792 2 0 -0.466362
10 37.8255 22.6271 24.0279 143663 2 0 0.129315
10 37.8451 22.7506 24.027 138989 2 0 0.100542
10 37.8799 25.5668 24.0193 150226 2 0 -0.397774
10 37.969 23.2135 24.0273 142995 2 0 -0.0192855
10 37.9754 22.6288 24.0265 137301 2 0 0.10287
10 37.9811 23.2854 24.0283 145294 2 0 -0.0461542
10 37.9919 22.873 24.0271 132010 2 0 0.0570142
10 37.9966 23.092 24.0281 136766 2 0 -0.0185658
10 38.0328 22.8404 24.0265 141557 2 0 0.0391784
10 38.0953 22.8757 24.0231 133214 2 0 -0.0510545Selected Spatial Ranges
Use RAMSES Standard Notation
Ranges correspond to the domain [0:1]^3 and are related to the box corner at [0., 0., 0.] by default.
particles = getparticles( info,
xrange=[0.2,0.8],
yrange=[0.2,0.8],
zrange=[0.4,0.6]); [Mera]: Get particle data: 2023-04-10T11:10:29.091
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(1, 2, 3, 4, 7) = (:vx, :vy, :vz, :mass, :birth)
domain:
xmin::xmax: 0.2 :: 0.8 ==> 9.6 [kpc] :: 38.4 [kpc]
ymin::ymax: 0.2 :: 0.8 ==> 9.6 [kpc] :: 38.4 [kpc]
zmin::zmax: 0.4 :: 0.6 ==> 19.2 [kpc] :: 28.8 [kpc]
Found 5.444850e+05 particles
Memory used for data table :38.42701530456543 MB
-------------------------------------------------------The loaded data ranges are assigned to the field ranges as an array in RAMSES standard notation (domain: [0:1]^3):
particles.ranges6-element Vector{Float64}:
0.2
0.8
0.2
0.8
0.4
0.6Ranges relative to a given center:
particles = getparticles( info,
xrange=[-0.3, 0.3],
yrange=[-0.3, 0.3],
zrange=[-0.1, 0.1],
center=[0.5, 0.5, 0.5]);[Mera]: Get particle data: 2023-04-10T11:10:33.971
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(1, 2, 3, 4, 7) = (:vx, :vy, :vz, :mass, :birth)
center: [0.5, 0.5, 0.5] ==> [24.0 [kpc] :: 24.0 [kpc] :: 24.0 [kpc]]
domain:
xmin::xmax: 0.2 :: 0.8 ==> 9.6 [kpc] :: 38.4 [kpc]
ymin::ymax: 0.2 :: 0.8 ==> 9.6 [kpc] :: 38.4 [kpc]
zmin::zmax: 0.4 :: 0.6 ==> 19.2 [kpc] :: 28.8 [kpc]
Found 5.444850e+05 particles
Memory used for data table :38.42701530456543 MB
-------------------------------------------------------Use notation in physical units
In the following example the ranges are given in unit "kpc", relative to the box corner 0., 0., 0.:
particles = getparticles( info,
xrange=[2.,22.],
yrange=[2.,22.],
zrange=[22.,26.],
range_unit=:kpc); [Mera]: Get particle data: 2023-04-10T11:10:40.217
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(1, 2, 3, 4, 7) = (:vx, :vy, :vz, :mass, :birth)
domain:
xmin::xmax: 0.0416667 :: 0.4583333 ==> 2.0 [kpc] :: 22.0 [kpc]
ymin::ymax: 0.0416667 :: 0.4583333 ==> 2.0 [kpc] :: 22.0 [kpc]
zmin::zmax: 0.4583333 :: 0.5416667 ==> 22.0 [kpc] :: 26.0 [kpc]
Found 3.091600e+04 particles
Memory used for data table :2.1834754943847656 MB
-------------------------------------------------------The possible physical length units for the keyword range_unit are defined in the field scale :
viewfields(info.scale) # or e.g.: gas.info.scale[Mera]: Fields to scale from user/code units to selected units
=======================================================================
Mpc = 0.0010000000000006482
kpc = 1.0000000000006481
pc = 1000.0000000006482
mpc = 1.0000000000006482e6
ly = 3261.5637769461323
Au = 2.0626480623310105e23
km = 3.0856775812820004e16
m = 3.085677581282e19
cm = 3.085677581282e21
mm = 3.085677581282e22
μm = 3.085677581282e25
Mpc3 = 1.0000000000019446e-9
kpc3 = 1.0000000000019444
pc3 = 1.0000000000019448e9
mpc3 = 1.0000000000019446e18
ly3 = 3.469585750743794e10
Au3 = 8.775571306099254e69
km3 = 2.9379989454983075e49
m3 = 2.9379989454983063e58
cm3 = 2.9379989454983065e64
mm3 = 2.937998945498306e67
μm3 = 2.937998945498306e76
Msol_pc3 = 0.9997234790001649
Msun_pc3 = 0.9997234790001649
g_cm3 = 6.76838218451376e-23
Msol_pc2 = 999.7234790008131
Msun_pc2 = 999.7234790008131
g_cm2 = 0.20885045168302602
Gyr = 0.014910986463557083
Myr = 14.910986463557084
yr = 1.4910986463557083e7
s = 4.70554946422349e14
ms = 4.70554946422349e17
Msol = 9.99723479002109e8
Msun = 9.99723479002109e8
Mearth = 3.329677459032007e14
Mjupiter = 1.0476363431814971e12
g = 1.9885499720830952e42
km_s = 65.57528732282063
m_s = 65575.28732282063
cm_s = 6.557528732282063e6
nH = 30.987773856809987
erg = 8.551000140274429e55
g_cms2 = 2.9104844143584656e-9
T_mu = 517028.3199143136
K_mu = 517028.3199143136
T = 680300.4209398864
K = 680300.4209398864
Ba = 2.910484414358466e-9
g_cm_s2 = 2.910484414358466e-9
p_kB = 2.1080995598777838e7
K_cm3 = 2.1080995598777838e7Ranges relative to the given center e.g. in unit "kpc":
particles = getparticles( info,
xrange=[-16.,16.],
yrange=[-16.,16.],
zrange=[-2.,2.],
center=[50.,50.,50.],
range_unit=:kpc); [Mera]: Get particle data: 2023-04-10T11:10:45.564
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(1, 2, 3, 4, 7) = (:vx, :vy, :vz, :mass, :birth)
center: [1.0416667, 1.0416667, 1.0416667] ==> [50.0 [kpc] :: 50.0 [kpc] :: 50.0 [kpc]]
domain:
xmin::xmax: 0.7083333 :: 1.0 ==> 34.0 [kpc] :: 48.0 [kpc]
ymin::ymax: 0.7083333 :: 1.0 ==> 34.0 [kpc] :: 48.0 [kpc]
zmin::zmax: 1.0 :: 1.0 ==> 48.0 [kpc] :: 48.0 [kpc]
Found 0.000000e+00 particles
Memory used for data table :1.71484375 KB
-------------------------------------------------------Use the short notation for the box center :bc or :boxcenter for all dimensions (x,y,z):
particles = getparticles( info,
xrange=[-16.,16.],
yrange=[-16.,16.],
zrange=[-2.,2.],
center=[:boxcenter],
range_unit=:kpc); [Mera]: Get particle data: 2023-04-10T11:10:48.345
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(1, 2, 3, 4, 7) = (:vx, :vy, :vz, :mass, :birth)
center: [0.5, 0.5, 0.5] ==> [24.0 [kpc] :: 24.0 [kpc] :: 24.0 [kpc]]
domain:
xmin::xmax: 0.1666667 :: 0.8333333 ==> 8.0 [kpc] :: 40.0 [kpc]
ymin::ymax: 0.1666667 :: 0.8333333 ==> 8.0 [kpc] :: 40.0 [kpc]
zmin::zmax: 0.4583333 :: 0.5416667 ==> 22.0 [kpc] :: 26.0 [kpc]
Found 5.445150e+05 particles
Memory used for data table :38.42913246154785 MB
-------------------------------------------------------particles = getparticles( info,
xrange=[-16.,16.],
yrange=[-16.,16.],
zrange=[-2.,2.],
center=[:bc],
range_unit=:kpc); [Mera]: Get particle data: 2023-04-10T11:10:50.163
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(1, 2, 3, 4, 7) = (:vx, :vy, :vz, :mass, :birth)
center: [0.5, 0.5, 0.5] ==> [24.0 [kpc] :: 24.0 [kpc] :: 24.0 [kpc]]
domain:
xmin::xmax: 0.1666667 :: 0.8333333 ==> 8.0 [kpc] :: 40.0 [kpc]
ymin::ymax: 0.1666667 :: 0.8333333 ==> 8.0 [kpc] :: 40.0 [kpc]
zmin::zmax: 0.4583333 :: 0.5416667 ==> 22.0 [kpc] :: 26.0 [kpc]
Found 5.445150e+05 particles
Memory used for data table :38.42913246154785 MB
-------------------------------------------------------Use the box center notation for individual dimensions, here x,z:
particles = getparticles( info,
xrange=[-16.,16.],
yrange=[-16.,16.],
zrange=[-2.,2.],
center=[:bc, 50., :bc],
range_unit=:kpc); [Mera]: Get particle data: 2023-04-10T11:10:53.187
Key vars=(:level, :x, :y, :z, :id, :family, :tag)
Using var(s)=(1, 2, 3, 4, 7) = (:vx, :vy, :vz, :mass, :birth)
center: [0.5, 1.0416667, 0.5] ==> [24.0 [kpc] :: 50.0 [kpc] :: 24.0 [kpc]]
domain:
xmin::xmax: 0.1666667 :: 0.8333333 ==> 8.0 [kpc] :: 40.0 [kpc]
ymin::ymax: 0.7083333 :: 1.0 ==> 34.0 [kpc] :: 48.0 [kpc]
zmin::zmax: 0.4583333 :: 0.5416667 ==> 22.0 [kpc] :: 26.0 [kpc]
Found 2.078000e+03 particles
Memory used for data table :151.8828125 KB
-------------------------------------------------------