How to write a program in Matlab which takes as input a student’s grade (such as ‘81’) and return a new grade in the A,B,C etc scale?

Here is the scale: A-=90-92 B+=87-89 B=83-86 B-=80-82 C+=77-79 C=73-76 C-=70-72 D+=67-69 D=64-66 F=0-63

[Adam]

What have you tried? Or did you just come straight here as soon as you got the question?

[Jocasta Oliveira]

[Thorsten]

You should replace

 grad = input('Grad>')

with

 grad = input('Please enter a numerical grad >')

and then do so when running the program. You tried to call clear when your are expected to provide the grad number as input.

Answer 1

[Thorsten]

grad = input('Grad> ')
if grad >= 90
 newgrad = 'A-';
elseif grad >= 87
 newgrad = 'B+';
elseif ...

or write a function

 function newgrad = getgrad(grad)
 if grad >= 90...

Answer 2

[Stephen23]

Or fully vectorized using histc:

>> inp = [95,16,85,50,75]; % example values
>> V = [-Inf,64,  67,  70, 73,  77,  80, 83,  87,90,Inf];
>> C = {'F','D','D+','C-','C','C+','B-','B','B+','A-'};
>> [~,X] = histc(inp,V);
>> out = C(X);
>> out{:}
ans = A-
ans = F
ans = B
ans = F
ans = C