Why Matlab does not read the input value?

Hello to everyone, I've got this problem with a programm that deal with autonomous driving...In particular within the function that take into account the acceleration of the leader vehicle, i'm trying to implement a constant deceleration of the vehicle from a cruice velocity of 10 m/s to 0. But in this case I'm considering that the car is not riding on a flat path but along a slope. I would like to have a deceleration of 0.1 regardless the grade.

t_stop=100;
slope_perc=input('put the % value of the slop= ');

theta=atan(slope_perc/100);

delta=0.1 +9.81*sin(theta);

if t<t_stop
    alead=-9.81*sin(theta)-delta;
else
    alead=0;
end

When I run the code matlab asks me "put the % value of the slope= " but when I insert the value, the programm doesn't go on and keeps asking always to put the value...I know that you should read all the code but, according to you, have I write something wrong? Thanks.

[Matt J]

Here's what I get,

put the percentual value of the slope= 3

Undefined function or variable 'pendenza_perc'.

Error in test (line 3)
theta=atan(pendenza_perc/100);

[Federico Ferrara]

i've corrected the word, sorry, it was written in italian before

Answer 1

[Jan]

This piece of code is called repeatedly. This shown code seems to be fine, so the behavior is caused the code, which calls this piece.