While running program it shows warning Matrix is singular close to singular or badly scaled. RCOND = NaN

Can any one help me in this regard. The coding is cost = [24.3891 25.5472 0.0253 24.4110 25.6753 0.0265 24.6382 25.8027 0.0280 24.7605 25.9318 0.0284 24.8882 26.0611 0.0285 118.9083 37.9637 0.0156 118.4576 37.7770 0.0136 118.9083 37.9637 0.0116 119.4576 38.7770 0.0106 81.8259 13.5073 0.0096 81.1364 13.3272 0.0088 81.2980 13.3538 0.0089 81.6259 13.4073 0.0093 217.8952 18.0000 0.0062 219.7752 18.6000 0.0060 218.3350 18.1000 0.0061 216.7752 18.2800 0.0059 218.7752 18.2000 0.0060 216.7752 17.2800 0.0058 142.7348 10.7367 0.0048 143.0288 10.7154 0.0047 143.3179 10.7367 0.0048 143.5972 10.7583 0.0049 259.1310 23.0000 0.0026 259.6490 23.1000 0.0026 260.1760 23.2000 0.0026 260.5760 23.4000 0.0026 261.1760 23.5000 0.0027 260.0760 23.0400 0.0026 176.0575 10.8416 0.0015 310.0021 7.4921 0.0019 311.9102 7.5031 0.0019];

mwlimits=[2.40 12 2.40 12 2.40 12 2.40 12 2.40 12 4.00 20 4.00 20 4.00 20 4.00 20 15.20 76 15.20 76 15.20 76 15.20 76 25.00 100 25.00 100 25.00 100 25.00 100 25.00 100 25.00 100 54.25 155 54.25 155 54.25 155 54.25 155 68.95 197 68.95 197 68.95 197 68.95 197 68.95 197 68.95 197 140.00 350 100.00 400 100.00 400];

Pdt = 2457;

dispatch gencost.

The warning occurs in getting PP=E\Dx' in dispatch program