Recent set representation changes added bugs in existing examples

[ttj]

The latest changes have introduced problems in existing examples, please revise and debug, this occurred both in my local matlab as well as codeocean. I would suggest going through all the examples and checking them.

Example file with bugs now is:

https://github.com/verivital/nnv/blob/master/code/nnv/examples/Submission/CAV2020/ACC/verify_nonlinear_ACC.m

Error log:

    'Table 3 (nonlinear plant): Generating ACC results for nonlinear plant model'

Reachability analysis for the controller 

Computing reach set for Layer 1 ...Error using Star/estimateRange (line 990)
Index exceeds the number of array elements (0).

Error in Star/estimateRanges (line 1049)
                    [lb(i), ub(i)] = obj.estimateRange(i);

Error in PosLin.reach_star_exact (line 152)
                [lb, ub] = I.estimateRanges;

Error in PosLin.reach_star_exact_multipleInputs (line 205)
                     S = [S PosLin.reach_star_exact(In(i), [])];

Error in PosLin.reach (line 745)
                R = PosLin.reach_star_exact_multipleInputs(I, option);

Error in LayerS/reach (line 117)
                parfor i=1:n

Error in FFNNS/reach (line 285)
                In = obj.Layers(i).reach(In, obj.reachMethod, obj.reachOption);

Error in NonlinearNNCS/reach (line 149)
                 [U,~] = obj.controller.reach(input_set, 'exact-star', n_cores); % control set at step i

Error in NonlinearNNCS/verify (line 634)
            obj.reach(reachPRM);

Error in verify_nonlinear_ACC (line 102)
    [safe{i}, counterExamples{i}, VT(i)] = ncs.verify(reachPRM, unsafeRegion);

Error in reproduce (line 38)
verify_nonlinear_ACC;
 
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