The MOSEK Python optimizer API manual Version 7.0 (Revision 141)

48 CHAPTER 5. BASIC API TUTORIAL
126 if e.msg is not None:
127 import traceback
128 traceback.print exc()
129 print ("\t%s" % e.msg)
130 sys.exit(1)
131 except:
132 import traceback
133 traceback.print exc()
134 sys.exit(1)
135 print ("Finished OK")
136 sys.exit(0)
5.5.1.2 Example code comments
Most of the functionality in this example has already been explained for the linear optimization example
in Section 5.2 and it will not be repeated here.
This example introduces one new function, Task.putqobj, which is used to input the quadratic terms
of the objective function.
Since Q o is symmetric only the lower triangular part of Q o is inputted.
computed by MOSEK using the relation
The upper part of Q o is
Q o ij = Q o ji.
Entries from the upper part may not appear in the input.
The lower triangular part of the matrix Q o is specified using an unordered sparse triplet format (for
details, see Section 5.13.3):
84 qsubi = [ 0, 1, 2, 2 ]
85 qsubj = [ 0, 1, 0, 2 ]
86 qval = [ 2.0, 0.2, -1.0, 2.0 ]
[ qo1.py ]
Please note that
• only non-zero elements are specified (any element not specified is 0 by definition),
• the order of the non-zero elements is insignificant, and
• only the lower triangular part should be specified.
Finally, the matrix Q o is loaded into the task:
88 task.putqobj(qsubi,qsubj,qval)
[ qo1.py ]