Is there a mistake with my code to calculate ballistic trajectory?

Question

Jose De La Pena 2019-12-9

0
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https://ww2.mathworks.cn/matlabcentral/answers/495595-is-there-a-mistake-with-my-code-to-calculate-ballistic-trajectory

回答： Hiro Yoshino 2019-12-9

function [x,y]= DeLaPena_Trajectory(velocity,angle)
%Fucntion that calculates x and y position of ball
%Inputs: Velocity(m/s) and Angle(degrees)
%Outputs: [x,y]
narginchk(2,2)
 
%Check for valid inputs
if velocity<0
    error('Velocity must be a positive number')
end 
if angle<0
    error('Angle must be positive')
end 
%Defines the velocities
v_x= velocity*cosd(angle); %x-component of v
v_y= velocity*sind(angle); %y-component of v
%Define the displacement equations and time equations 
t= (2*v_y)/9.81; %time of ballistic
x= v_x*t; %x-location
y= v_y*t-(1/2)*9.81*t^2; %y-location

This is my user-defined function for ballistic trajectory is there anything wrong with my code, I dont get the same answers as I would when I do it by hand.