# Cannot able to rotate turtlesim

Hi everyone, I am trying to write simple code to rotate Turtlesim robot with the folllowing code but it is not working with double values, let me explain it, I wrote this code to move straight and rotate:

```
#include "ros/ros.h"
#include "geometry_msgs/Twist.h"
#include "turtlesim/Pose.h"
#include <sstream>
ros::Publisher velocity_publisher;
ros::Subscriber pose_subscriber;
turtlesim::Pose turtlesim_pose;
const double x_min = 0.0;
const double y_min = 0.0;
const double x_max = 11.0;
const double y_max = 11.0;
const double pi = 3.14159265359;
void move(double speed, double distance, bool isForward);
void rotate(double angular_speed, double angle, bool clockwise);
int main(int argc, char **argv)
{
double speed, angular_speed, angular_speed_degree;
double distance, angle, angle_degree;
bool isForward, clockwise;
ros::init(argc, argv,"robot_cleaner");
ros::NodeHandle n;
velocity_publisher = n.advertise<geometry_msgs::Twist>("/turtle1/cmd_vel", 10);
std::cout << "Enter the speed: ";
std::cin >> speed;
std::cout << "Enter the distance: ";
std::cin >> distance;
std::cout << "Forward?";
std::cin >> isForward;
move(speed, distance, isForward);
std::cout << "Enter angular speed:";
std::cin >> angular_speed_degree;
angular_speed = angular_speed_degree * 3.14 /180; // Degrees to Radians
std::cout << "Enter desired angle:";
std::cin >> angle_degree;
angle = angle_degree * 3.14/ 180; // Degrees to Radians
std::cout << "Clockwise?";
std::cin >> clockwise;
rotate(angular_speed,angle,clockwise);
ros::spin();
return 0;
}
```

The move() function works well, but in rotate function I have problems. If I wrote parameters by myself It work well for example:

```
std::cout << "Enter angular speed:";
std::cin >> angular_speed_degree;
std::cout << "Enter desired angle:";
std::cin >> angle_degree;
std::cout << "Clockwise?";
std::cin >> clockwise;
rotate(angular_speed,angle,clockwise);
```

This code works well but, when I try to make a conversion like above code, degree to radian rotate() function fails, the rotate function is in below:

```
void rotate(double angular_speed, double angle, bool clockwise)
{
// angle = angular_speed * time
geometry_msgs::Twist vel_msg;
// set a random linear velocity in the x-axis
vel_msg.linear.x = 0;
vel_msg.linear.y = 0;
vel_msg.linear.z = 0;
// set angular velocity
vel_msg.angular.x = 0;
vel_msg.angular.y = 0;
if(clockwise)
vel_msg.angular.z = -abs(angular_speed);
else
vel_msg.angular.z = abs(angular_speed);
// t0 is the current time
double t0 = ros::Time::now().toSec();
double current_angle = 0;
ros::Rate loop_rate(10);
// loop to publish the velocity
// estimate, current_distance = velocity * (t1 - t0)
do
{
// Publish the velocity
velocity_publisher.publish(vel_msg);
// t1 is the current time
double t1 = ros::Time::now().toSec();
// Calculate current_distance
current_angle = angular_speed * (t1 - t0) ;
ros::spinOnce();
loop_rate.sleep();
} while (current_angle < angle);
// set velocity to zero to stop the robot
vel_msg.angular.z = 0.0;
velocity_publisher.publish(vel_msg);
}
```

Could you please help me to find the reason of this problem, please?