# How to save only the particles that contain in the box below ?

Asked by Bowonchanok Maneerat on 2020-04-14

Now I am creating a box that contains particles and in the box there are two box other box overlapping each other. So I compaction the particle til it should have maximum density . After that I use the order that remove the box on top so that I can use only the particles that contain in the box below.

After that I want to save the particles or sphere in the box below that are left by using an order export.text() to save the particles. But there was a problem in the order that it save the particles that contain in both boxes but I only want to save the particles that contain in the box below. Do you have a suggestion how to save only the particles that contain in the box below ?

this is my code :
import matplotlib.pyplot as plt
import math

O.materials.append(FrictMat(young=20e10,density=7860,label="steel"))

# create rectangular box from boxes (maybe there is some library function, but I did not find it quickly)
cx,cy,cz = 6.3,6.3,6.3 # center of the box
dx,dy,dz = 7.5,7.5,7.5 # half-dimensions of the box
t = 0.25 # half-thickness of walls
left = box((cx-dx-t+1.2,cy+1.2,cz),(t,dy+2*t,cz),fixed=True,wire=True,material="steel")
right = box((cx+dx+t+1.2,cy+1.2,cz),(t,dy+2*t,cz),fixed=True,wire=True,material="steel")
front = box((cx+1.2,cy-dy-t+1.2,cz),(dx,t,cz),fixed=True,wire=True,material="steel")
back = box((cx+1.2,cy+dy+t+1.2,cz),(dx,t,cz),fixed=True,wire=True,material="steel")
bottom = box((cx+1.2,cy+1.2,cz-dz-t+1.2),(dx+2*t,dy+2*t,t),fixed=True,wire=True,material="steel")

left2 = box((cx-dx-t+1.2,cy+1.2,cz*2+2.7),(t,dy+2*t,2.7),fixed=True,wire=True,material="steel")
right2 = box((cx+dx+t+1.2,cy+1.2,cz*2+2.7),(t,dy+2*t,2.7),fixed=True,wire=True,material="steel")
front2 = box((cx+1.2,cy-dy-t+1.2,cz*2+2.7),(dx,t,2.7),fixed=True,wire=True,material="steel")
back2 = box((cx+1.2,cy+dy+t+1.2,cz*2+2.7),(dx,t,2.7),fixed=True,wire=True,material="steel")

top2 = box((cx+1.2,cy+1.2,18+t),(dx,dy,t),fixed=True)
Boxids=O.bodies.append((left,right,back,front,left2,right2,back2,front2,bottom))

O.bodies.append(ymport.text('minmin'))

O.engines=[
ForceResetter(),
InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Box_Aabb()]),
InteractionLoop(
[Ig2_Sphere_Sphere_ScGeom(),Ig2_Box_Sphere_ScGeom()],
[Ip2_FrictMat_FrictMat_FrictPhys()],
[Law2_ScGeom_FrictPhys_CundallStrack()]
),
NewtonIntegrator(gravity=(0,0,-9.81),damping=0.4),
TranslationEngine(translationAxis=[0,1,0],velocity=5.0,ids=Boxids[4:8]),
PyRunner(command='check()',iterPeriod=1000,label='checker')
]

O.dt=PWaveTimeStep()

def check() :
if O.bodies.state.pos>20:
O.pause()
bb=[]
for b in O.bodies:
if isinstance(b.shape,Sphere):
if b.state.pos>=0 and b.state.pos<=15:
if b.state.pos>=0 and b.state.pos<=15:
if b.state.pos>=0 and b.state.pos<=12.6:
bb.append(b)
nb=len(bb)
vs=nb*(4.0/3)*pi*(0.2**3)
ms=1800*1e-6*vs
V=15*15*12.6*1e-6
Densitymin=ms/V
unitweightmin=(ms*9.81)/V
print('Densitymin =', Densitymin)
print('Unitweightmin =', unitweightmin)
print('Volume of soil =', vs)
print('Mass of soil =', ms)
print('Volume of specimen',V)
print('Number of sphere in specimen', nb)

## Question information

Language:
English Edit question
Status:
Solved
For:
Assignee:
No assignee Edit question
Solved by:
Jan Stránský
Solved:
2020-04-14
Last query:
2020-04-14
2020-04-14 Jan Stránský (honzik) said on 2020-04-14: #1

Hello,

> order

"command" is more suitable English word

> Do you have a suggestion how to save only the particles that contain in the box below ?

You have several options, e.g. save the packing "manually":
###
def particles_that_contain_in_the_box_below():
ret = []
for b in O.bodies:
if not isinstance(b.shape,Sphere): continue # skip non-spherical, not clear if yes or not
if b.state.pos < 1: # for example, replace by your "contain in the box below" condition
ret.append(b)
return ret

particles = particles_that_contain_in_the_box_below()
with open("particles_that_contain_in_the_box_below.dat","w") as f:
for particle in particles:
x,y,z = p.state.pos
###

cheers
Jan

 Bowonchanok Maneerat (lnwnew5555) said on 2020-04-14: #2

thanks jan

cheer

 Bowonchanok Maneerat (lnwnew5555) said on 2020-04-14: #3

Thanks Jan Stránský, that solved my question.