PoseOptimization()

[NCHUPJ]

The following error occurred during G2O debugging,how to solve it?
iteration= 1 chi2= -nan time= 0.000213322 cumTime= 0.00058214 edges= 264 schur= 0 lambda= nan levenbergIter= 1 iteration= 2 chi2= -nan time= 0.000207232 cumTime= 0.000789372 edges= 264 schur= 0 lambda= nan levenbergIter= 1 iteration= 3 chi2= -nan time= 0.000203211 cumTime= 0.000992583 edges= 264 schur= 0 lambda= nan levenbergIter= 1 iteration= 4 chi2= -nan time= 0.000202551 cumTime= 0.00119513 edges= 264 schur= 0 lambda= nan levenbergIter= 1 iteration= 5 chi2= -nan time= 0.00020326 cumTime= 0.00139839 edges= 264 schur= 0 lambda= nan levenbergIter= 1 iteration= 6 chi2= -nan time= 0.000205994 cumTime= 0.00160439 edges= 264 schur= 0 lambda= nan levenbergIter= 1 iteration= 7 chi2= -nan time= 0.000214187 cumTime= 0.00181857 edges= 264 schur= 0 lambda= nan levenbergIter= 1 iteration= 8 chi2= -nan time= 0.000200907 cumTime= 0.00201948 edges= 264 schur= 0 lambda= nan levenbergIter= 1 iteration= 9 chi2= -nan time= 0.000200807 cumTime= 0.00222029 edges= 264 schur= 0 lambda= nan levenbergIter= 1