[Coin-ipopt] Least square system singular while initializing equality multipliers.

[Nguyen An Danh]

Dear Andreas,

Could you tell me about the message: "Least square system singular while 
initializing equality multipliers." ?

I am now executing another problem (please see below).  I do not know why I 
can not excute the problem.  Although the total of variables is small.

I reread your instruction about ||C||, and try to follow your tips to choose a 
better starting point.  But I failed!!!  It 's really very stuff to choose 
suitable starting point.

Thank you so much.

Parameter IMAXITER             has multiple assignments - using  0.10000D+05 .
******************************************************************************
This program contains IPOPT, a program for large-scale nonlinear optimization.
   IPOPT is released as open source under the Common Public License (CPL).
               For more information visit www.coin-or.org/Ipopt
******************************************************************************

  Going to allocate double precision work space of size         10795497
                             integer work space of size         15870830


Number of variables           :    86017
   of which are fixed         :        0
Number of constraints         :    17333
Number of lower bounds        :        1
Number of upper bounds        :    12288
Number of nonzeros in Jacobian:  1606464
Number of nonzeros in Hessian :   331777
 get_scale: |g|_inf =     1.0000000000000
 get_scale: QFSCALE =     1.0000000000000
 get_scale: smallest CSCALE =    0.24641104282206

ITER     ERR       MU      ||C||   ||YPY||  ||PZ||     ||D||   ALFA(V)   
ALFA(X)     NU   #LS       F      #cor   Regu    CPU(s)
    0 .400D+05p .100D+00 .427D+07 .000D+00 .000D+00  .000D+00 .000D+00  .000D
+00  .000D+00  0 -.51601698D+03  0 .000D+00 .205D+03
Least square system singular while initializing equality multipliers.
Setting multipliers to zero.
 ma27_call:  LIWMA increased from  5103977 to  26726960
 ma27_call:  LA increased from  8063622 to  26726960
 ma27_call:  LIWMA increased from  26726960 to  67659177
 ma27_call:  LA increased from  26726960 to  67659177
 ma27_call:  LIWMA increased from  67659177 to  172652595
 ma27_call:  LA increased from  67659177 to  172652595