title: Error: InvalidPipeArgument: 'undefined is not a number' for pipe 'DecimalPipe'
body: <p>I have this input : 
  <code>&lt;input class="number " type= "text"  pInputText [readonly]="" formControlName="id" [required]="" plmNumberFormatter [value]="data?.id   | numberPipe" /&gt;</code></p>
  
  <p>When putting the cursor on the input I get undefined as a value in the input. </p>
  
  <p>This my TS : </p>
  
  <pre><code>ngOnInit() {
      this.form = this.createForm();
      this.keys.split(',').forEach(item =&gt; {
        set(this.data, item, null);
      });
  </code></pre>
  
  <p>and this is my pipe : </p>
  
  <pre><code>transform(value: number | string, fractionSize?: number): string {
        const numberValue = transformToNumber(value, this.profile.getCurrentProfile());
      let retNumber = Number(numberValue);
        return this.decimalPipe.transform(retNumber,  this.profile.getDigitsInfo(), this.profile.getLocale());
    }
  </code></pre>
  
  <p>What is wrong? </p>
  
  <p>Angular version: 7.3.9</p>