def get_image_size( imgdata, myid ):
from mpi import mpi_gather, mpi_bcast, MPI_COMM_WORLD, MPI_INT
nimg = len(imgdata)
nimgs = mpi_gather( nimg, 1, MPI_INT, 1, MPI_INT, 0, MPI_COMM_WORLD )
if myid==0:
src = -1
for i in xrange( len(nimgs) ):
if int(nimgs[i]) > 0 :
src = i
break
if src==-1:
return 0
else:
src = -1
size_src = mpi_bcast( src, 1, MPI_INT, 0, MPI_COMM_WORLD )
if myid==int(size_src[0]):
assert nimg > 0
size = imgdata[0].get_xsize()
else:
size = -1
nx = mpi_bcast( size, 1, MPI_INT, size_src[0], MPI_COMM_WORLD )
return int(nx[0])
def get_image_size(imgdata, myid):
from mpi import mpi_gather, mpi_bcast, MPI_COMM_WORLD, MPI_INT
nimg = len(imgdata)
nimgs = mpi_gather(nimg, 1, MPI_INT, 1, MPI_INT, 0, MPI_COMM_WORLD)
if myid == 0:
src = -1
for i in xrange(len(nimgs)):
if int(nimgs[i]) > 0:
src = i
break
if src == -1:
return 0
else:
src = -1
size_src = mpi_bcast(src, 1, MPI_INT, 0, MPI_COMM_WORLD)
if myid == int(size_src[0]):
assert nimg > 0
size = imgdata[0].get_xsize()
else:
size = -1
nx = mpi_bcast(size, 1, MPI_INT, size_src[0], MPI_COMM_WORLD)
return int(nx[0])
count = 4
# in python we do not need to preallocate the array myray
# we do need to assign a dummy value to the send_ray
send_ray = zeros(0, "i")
if myid == mpi_root:
size = count * numnodes
send_ray = zeros(size, "i")
for i in range(0, size):
send_ray[i] = i
#send different data to each processor
myray = mpi.mpi_scatter(send_ray, count, mpi.MPI_INT, count, mpi.MPI_INT,
mpi_root, mpi.MPI_COMM_WORLD)
#each processor does a local sum
total = 0
for i in range(0, count):
total = total + myray[i]
print "myid=", myid, "total=", total
#gather back to the root and sum/print
back_ray = mpi.mpi_gather(total, 1, mpi.MPI_INT, 1, mpi.MPI_INT, mpi_root,
mpi.MPI_COMM_WORLD)
if myid == mpi_root:
total = 0
for i in range(0, numnodes):
total = total + back_ray[i]
print "results from all processors=", total
mpi.mpi_finalize()
mpi_root = 0
myid = mpi.mpi_comm_rank(mpi.MPI_COMM_WORLD)
numnodes = mpi.mpi_comm_size(mpi.MPI_COMM_WORLD)
print "hello from ", myid, " of ", numnodes
mysize = myid + 1
myray = zeros(mysize, "i")
for i in range(0, mysize):
myray[i] = myid + 1
if myid == mpi_root:
displacements = zeros(numnodes, "i")
else:
displacements = zeros(0, "i")
#myray[0] contains the number of values we will send in the gatherv
counts = mpi.mpi_gather(myray[0], 1, mpi.MPI_INT, 1, mpi.MPI_INT, mpi_root,
mpi.MPI_COMM_WORLD)
if myid == mpi_root:
displacements[0] = 0
for i in range(1, numnodes):
displacements[i] = counts[i - 1] + displacements[i - 1]
size = 0
for i in range(0, numnodes):
size = size + counts[i]
allray = mpi.mpi_gatherv(myray, mysize, mpi.MPI_INT, counts, displacements,
mpi.MPI_INT, mpi_root, mpi.MPI_COMM_WORLD)
if myid == mpi_root:
print "allrray= ", allray
import random
#print "before",len(sys.argv),sys.argv
sys.argv = mpi.mpi_init(len(sys.argv),sys.argv)
#print "after ",len(sys.argv),sys.argv
mpi_root=0
myid=mpi.mpi_comm_rank(mpi.MPI_COMM_WORLD)
numnodes=mpi.mpi_comm_size(mpi.MPI_COMM_WORLD)
print "hello from ",myid," of ",numnodes
mysize=myid+1
#mysize contains the number of values we will send in the scatterv
counts=mpi.mpi_gather(mysize,1,mpi.MPI_INT,1,mpi.MPI_INT, mpi_root,mpi.MPI_COMM_WORLD)
if myid != mpi_root:
displacements=zeros(0,"i")
sray=zeros(0,"i")
if myid == mpi_root:
print "counts=",counts
displacements=zeros(numnodes,"i")
displacements[0]=0
for i in range(1, numnodes):
displacements[i]=counts[i-1]+displacements[i-1]
size=0
for i in range(0, numnodes):
size=size+counts[i]
sray=zeros(size,"i")
for i in range(0, size):
count = 4
# in python we do not need to preallocate the array myray
# we do need to assign a dummy value to the send_ray
send_ray = zeros(0, "d")
if myid == mpi_root:
size = count * numnodes
send_ray = zeros(size, "d")
for i in range(0, size):
send_ray[i] = i
#send different data to each processor
myray = mpi.mpi_scatter(send_ray, count, mpi.MPI_DOUBLE, count, mpi.MPI_DOUBLE,
mpi_root, mpi.MPI_COMM_WORLD)
#each processor does a local sum
total = 0.0
for i in range(0, count):
total = total + myray[i]
print "myid=", myid, "total=", total
#gather back to the root and sum/print
back_ray = mpi.mpi_gather(total, 1, mpi.MPI_DOUBLE, 1, mpi.MPI_DOUBLE,
mpi_root, mpi.MPI_COMM_WORLD)
if myid == mpi_root:
total = 0.0
for i in range(0, numnodes):
total = total + back_ray[i]
print "results from all processors=", total
mpi.mpi_finalize()