optimization toolbox problem for a video system

Hi, I'm currently working on a video system and I code the resolution with Matlab. I saw that this subject had been already concerned but I didn't see the answer. I have this error message in my Matlab prompt : Attempt to reference field of non-structure array.

Error in optimget>optimgetfast (line 108) value = defaultopt.(name);

Error in optimget (line 25) o = optimgetfast(options,name,default);

Error in snls (line 95) mtxmpy = optimget(options,'JacobMult',defaultopt,'fast') ;

Error in lsqcurvefit (line 257) [x,FVAL,LAMBDA,JACOB,EXITFLAG,OUTPUT]=...

Error in solveTemplateGeom (line 81) [angles(aflags), resnorm, resids, exitflag, output, lambda, J] = ...

Error in Y:\ARGUS-pCode2010b\argusTools\autoGeom\doAutoGeom.p>doAutoGeom (line 137) [ag, stats] = solveTemplateGeom(I, t, g.geometry, g.camera, g.ip, aindex);

Error in Y:\ARGUS-pCode2010b\argusTools\autoGeom\doOneAutoGeom.p>doOneAutoGeom (line 30) [ag, stats] = doAutoGeom( name, id ); Is there someone who can help me? Thanks, Yohan