sphere_enclosing_points_api

Example Python program sphere_enclosing_points_api.py Python version 3.x or newer. To check the Python version use:

python --version

Modules

import sys
import mosek
import numpy as np
import plot

Methods

def streamprinter(text):

Code

Python example

import sys

import mosek 

import numpy as np

import plot


#--------------------------------------------------------
def streamprinter(text): 
    sys.stdout.write(text) 
    sys.stdout.flush()


k=int(sys.argv[1]) #number of points
n=int(sys.argv[2]) #dimension

p=  np.random.normal(size=(k,n))

env = mosek.Env()
task= env.Task(0,0)

numvar= 1 + n + k*n + k

offset_r= 0
offset_p= 1
offset_w= 1+n
offset_t= 1+n+n*k

task.appendvars(numvar)
task.putvarboundslice(0,numvar,[mosek.boundkey.fr for i in range(numvar)], np.zeros(numvar), np.zeros(numvar))


numcon= 2*k + k
task.appendcons(numcon)

for i in range(k):#for each point
    task.putarow(i, [0,i+offset_t], [1., -1,]) #delta coord#radius aux
    task.putconbound(i, mosek.boundkey.fx, 0. ,0.)

    for j in range(n):
        task.putconbound(k+ i*n + j, mosek.boundkey.fx, p[i][j] , p[i][j])
        task.putarow(k+i*n + j,[offset_p + j, offset_w+i*n + j],[1.0,-1.0])

    task.appendcone(mosek.conetype.quad,0., np.hstack([ offset_t+i, [ offset_w+i*n + j for j in range(n)]] ))

task.putcj(0,1.0)
task.putobjsense(mosek.objsense.minimize)

task.set_Stream (mosek.streamtype.log, streamprinter)
task.writedata("dump.opf")

task.optimize()

xx = np.zeros(numvar, float) 
task.getxx(mosek.soltype.itr,xx)

r0= xx[0]
p0= xx[1:n+1]

print(r0,p0)


#comment out this block if you haven't matplotlib installed
if n==2:
    plot.plot_points(p,p0,r0)

Useful Links

Articles: https://python-commandments.org/
Python shell: https://bsdnerds.org/learn-python/
Tutorial: https://pythonprogramminglanguage.com/