以太坊eth_sendTransaction RPC

Question

正在尝试使用PHP curl函数发送事务。但是在消息：非数组参数时出现错误。传递的参数是from，to，value（amount * 10 ^ 18）另外我想知道数据字段很重要吗？如果是，我该如何创建它。

是否缺少其他任何参数？请帮助我解决这个问题。

 function eth_sendTransaction($from_address,$to,$amount)
        {
            $data = array();
            $data['jsonrpc'] = $this->version;
            $data['id'] = $this->id++;
            $data['method'] = 'eth_sendTransaction';
            $transaction = array('from'=>$from_address,'to'=>$to,'value'=>(float)$amount);
            $data['params'] = $transaction;
            $ch = curl_init();
            curl_setopt($ch, CURLOPT_URL, $this->wallet_ip);
            curl_setopt($ch, CURLOPT_PORT, $this->wallet_port);
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
            curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/json')); 
            curl_setopt($ch, CURLOPT_POST, count($transaction));
            curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($data));
            $ret = curl_exec($ch);
            curl_close($ch);
    print_r($ret);
        }