step 1 - convert al lcomponents, directives and pipes to standalone

see https://v17.angular.io/guide/standalone-migration
I executed:
ng g @angular/core:standalone
and selected "Convert all components, directives and pipes to standalone"

pdb-js/src/app/y-axis-definition/y-axis-definition.component.spec.ts

@@ -8,8 +8,8 @@ describe('YAxisDefinitionComponent', () => {
 
   beforeEach(waitForAsync(() => {
     TestBed.configureTestingModule({
-      declarations: [ YAxisDefinitionComponent ]
-    })
+    imports: [YAxisDefinitionComponent]
+})
     .compileComponents();
   }));
 

pdb-js/src/app/y-axis-definition/y-axis-definition.component.ts

@@ -1,10 +1,18 @@
 import { Component,  Input } from '@angular/core';
 import { YAxisDefinition  } from '../plot.service';
+import { MatFormField, MatLabel } from '@angular/material/form-field';
+import { MatSelect } from '@angular/material/select';
+import { MatOption, MatOptgroup } from '@angular/material/core';
+import { NgIf } from '@angular/common';
+import { MatInput } from '@angular/material/input';
+import { FormsModule } from '@angular/forms';
 
 @Component({
-  selector: 'pdb-y-axis-definition',
-  templateUrl: './y-axis-definition.component.html',
-  styleUrls: ['./y-axis-definition.component.scss']
+    selector: 'pdb-y-axis-definition',
+    templateUrl: './y-axis-definition.component.html',
+    styleUrls: ['./y-axis-definition.component.scss'],
+    standalone: true,
+    imports: [MatFormField, MatLabel, MatSelect, MatOption, MatOptgroup, NgIf, MatInput, FormsModule]
 })
 export class YAxisDefinitionComponent {