title: TypeError: unsupported operand type(s) for +: 'int' and 'tuple'
body: <p>I'm trying to get the values of vector and degrees for each value of time but i get stuck with this error:</p>
  
  <blockquote>
    <p>TypeError: unsupported operand type(s) for +: 'int' and 'tuple'</p>
  </blockquote>
  
  <p>If i follow the traceback i get to x = -0,3*(t**2)+(7,2*t)+28 but how come that's a int = tuple?</p>
  
  <p>Traceback:</p>
  
  <pre><code>Traceback (most recent call last):
    File "testgraph.py", line 53, in &lt;module&gt;
      vector, degrees = vector_position(t)
    File "testgraph.py", line 14, in vector_position
      x = function_positionX(t)
    File "testgraph.py", line 5, in function_positionX
      x = -0,3*(t**2)+(7,2*t)+28 
  </code></pre>
  
  <p>Code:</p>
  
  <pre><code>import numpy as np
  import math
  
  def function_positionX(t):
      x = -0,3*(t**2)+(7,2*t)+28
      return x
  
  def function_positionY(t):
      y = 0,22*(t**2)-(9,1*t)+30
      return y
  
  def vector_position(t):
      x = function_positionX(t)
      y = function_positionY(t)
      v = math.sqrt((x**2)+(y**2))
      d = np.arctan2(y/x)
      return v,d
  
  def function_speedX(t):
      x = -0,62*t+7,2
      return x
  
  def function_speedY(t):
      y = 0,44*t-9,1
      return y
  
  def vector_speed(t):
      x = function_speedX(t)
      y = function_speedY(t)
      v = math.sqrt((x**2)+(y**2))
      d = np.arctan2(y/x)
      return v,d
  
  def function_accelX():
      a = -0,62
      return a
  
  def function_accelY():
      a = 0,44
      return a
  
  def vector_accel(t):
      x = function_accelX()
      y = function_accelY()
      v = math.sqrt((x**2)+(y**2))
      d = np.arctan2(y/x)
      return v,d
  
  
  for t in range(0,15):
      print("For time: ", t)
      vector, degrees = vector_position(t)
      print(vector,degrees)
      vector, degrees = vector_speed(t)
      print(vector,degrees)
      vector, degrees = vector_accel(t)
      print(vector,degrees)
  </code></pre>