Reading Serial Data from Matlab, not working as expected.

Hello I am sending a string data to Arduino from matlab using the following code.

clear s;
s=serial('COM4','BAUD', 9600); % Make sure the baud rate and COM port is                      
fopen(s);
value1=('11,222;333<444>555?666');

display('data sent');

fprintf(s,'%s\n',value1);

fclose(s);

I am receiving and processing the string in arduino using the following code

String command;
 int i;
float data_rec;
void setup() {
  // put your setup code here, to run once:
command="11,222;333<444>555?666";
Serial.begin(9600);

}


void loop() {

if(Serial.available() >0){
  String command=Serial.readString();
//  char c=Serial.read();
  //if(c == '\n'){
    parseCommand(command);
    data_rec=Serial.parseInt();
    Serial.println("data_rec");
    Serial.println(data_rec);
  //}
  
}
}

void parseCommand(String com){

  String F_d;
  String E_m;
  String L_p;
  String S_v;
  String H_d;
  String L_t;

  F_d=com.substring(0,com.indexOf(','));
  E_m=com.substring(com.indexOf(',')+1,com.indexOf(';'));
  L_p=com.substring(com.indexOf(';')+1,com.indexOf('<'));
  S_v=com.substring(com.indexOf('<')+1,com.indexOf('>'));
  H_d=com.substring(com.indexOf('>')+1,com.indexOf('?'));
  L_t=com.substring(com.indexOf('?')+1,com.length());

Serial.println(com);
 Serial.println("F_d:");
 Serial.println(F_d);
 Serial.println("E_m:");
 Serial.println(E_m);
 Serial.println("L_p:");
 Serial.println(L_p);
 Serial.println("S_v:");
 Serial.println(S_v);
 Serial.println("H_d:");
 Serial.println(H_d);
 Serial.println("L_t:");
 Serial.println(L_t);
}

This does not work with Matlab.,
However when I send the same string from the Serial Monitor, it seems to work.

Why ain’t I getting any output for the matlab code?
I am checking the data sent and received by arduino over serial by monitoring the serial port using Serial Monitoring Studio.

Why ain't I getting any output for the matlab code?

Why ain't you telling us what you DO get? Does the RX LED even flash?

Why does your code have TWO variables named command?

I don't know Matlab but the the examples in Serial Input Basics should be good for receiving the data.

It is not a good idea to use the String (capital S) class on an Arduino as it can cause memory corruption in the small memory on an Arduino. Just use cstrings - char arrays terminated with 0.

...R