fix bug of hyper-parameter graph when search space has loguniform type (#1399)

src/webui/src/components/trial-detail/Para.tsx

@@ -87,13 +87,10 @@ class Para extends React.Component<ParaProps, ParaState> {
                 let temp: Array<number> = [];
                 for (let i = 0; i < dimName.length; i++) {
                     if ('type' in parallelAxis[i]) {
-                        temp.push(
-                            eachTrialParams[item][dimName[i]].toString()
-                        );
+                        temp.push(eachTrialParams[item][dimName[i]].toString());
                     } else {
-                        temp.push(
-                            eachTrialParams[item][dimName[i]]
-                        );
+                        // default metric
+                        temp.push(eachTrialParams[item][dimName[i]]);
                     }
                 }
                 paraYdata.push(temp);
@@ -199,11 +196,18 @@ class Para extends React.Component<ParaProps, ParaState> {
                     break;
                 // support log distribute
                 case 'loguniform':
+                    if (lenOfDataSource > 1) {
                         parallelAxis.push({
                             dim: i,
                             name: dimName[i],
                             type: 'log',
                         });
+                    } else {
+                        parallelAxis.push({
+                            dim: i,
+                            name: dimName[i]
+                        });
+                    }
                     break;
 
                 default: