number_format(） 期望参数 1 为双精度，数组给定

我是拉拉维尔的新手，如果这个问题看起来很简单，我很抱歉。

我想显示给定月份和年份的credit_memo总和，但它显示错误："number_format（） 期望参数 1 为双精度，数组给定"，我不知道错误的来源是什么。

信用备忘录模型

<?php namespace App;
use Illuminate'Database'Eloquent'Model;
class CreditMemoModel extends Model{
    public $table = "credit_memo";
    public function getTotalAmount(){
        return $this->credit_memo()->total_amount;
    }
}
?>

CMController（只是与CreditMemo相关的）

use App'CreditMemoModel;
$credit_memos = CreditMemoModel::all();
$data               = [];
    foreach($date_arr as $date_index){
      foreach ($credit_memos as $credit_memo) {
            $data[$date_index]['credit_memos'][$credit_memo->total_amount] = 0;
        }
}

和视图

<td>Credit Memo</td>
        @foreach($date_arr as $date)
        <td class="text-right">{{ number_format($data[$date]['credit_memos'],2) }}</td>
        <?php $qtotal += $data[$date]['credit_memos']; ?>
      @endforeach
      <td class="text-right">{{number_format($qtotal, 2)}}</td>