Cannot read property '0' of undefined

Ionic Framework ionic-v3
1

TypeError: Cannot read property ‘0’ of undefined
at Object.View_ProductPage_3.currVal_0 [as updateDirectives] (ng:///AppModule/ProductPage.ngfactory.js:112:29)
at Object.debugUpdateDirectives [as updateDirectives] (http://localhost:8100/build/vendor.js:13450:21)
at checkAndUpdateView (http://localhost:8100/build/vendor.js:12627:14)
at callViewAction (http://localhost:8100/build/vendor.js:12995:21)
at execEmbeddedViewsAction (http://localhost:8100/build/vendor.js:12953:17)
at checkAndUpdateView (http://localhost:8100/build/vendor.js:12628:5)
at callViewAction (http://localhost:8100/build/vendor.js:12995:21)
at execEmbeddedViewsAction (http://localhost:8100/build/vendor.js:12953:17)
at checkAndUpdateView (http://localhost:8100/build/vendor.js:12628:5)
at callViewAction (http://localhost:8100/build/vendor.js:12995:21)

CODE:<ion-card col-12 text-center col-md-6 class=“mid” *ngFor = “let dime of dimensions;let i= index;trackBy: customTrackBy”>

<div *ngIf= “dime!=‘Dimensions X (Inches)’ && dime!=‘Dimensions Y (Inches)’”>

      <ion-row>
        <ion-col col-3 text-center col-md-3 class="mid">
              <label>
              {{dime}}
              </label>
        </ion-col>

        <ion-col col-3 text-center col-md-3 class="mid">

          <ion-input   name="dimx"   [(ngModel)]="dimx[i]" ></ion-input>
           
        </ion-col>
        <ion-col col-3 text-center col-md-3 class="mid">
           
                <ion-input  name="dimy"  [(ngModel)]="dimy[i]" ></ion-input>
            </ion-col>  
          
        
        <ion-col col-3 text-center col-md-3 class="mid">
            <ion-input type="text"  [readonly]="isReadonly()" [(ngModel)]="area[i]" ></ion-input>
        </ion-col>
        
      </ion-row>