I am trying to loop my if statement but I'm not sure how to

clc;

atomic_weight = [15.9994; 12.011; 14.00674; 32.066; 1.00794];
alanine = xlsread('lab12.xlsx','B4:F4');
arginine = xlsread('lab12.xlsx','B5:F5');
asparigine = xlsread('lab12.xlsx','B6:F6');
alaninemw = alanine*atomic_weight;
argininemw = arginine*atomic_weight;
aspariginemw = asparigine*atomic_weight;

file = input("Enter file name including file extension: \n",'s');
xlsx = 'xlsx';

while true

    if contains(file, xlsx)
        fprintf("The molecular weight of Alanine is %5f\n", alaninemw);
        fprintf("The molecular weight of Arginine is %5f\n", argininemw);
        fprintf("The molecular weight of Asparigine is %5f\n", aspariginemw);
    else
        false
    end
end

Answer 1

[David Hill]

xlsx = 'xlsx';
while true
    file = input("Enter file name including file extension: \n",'s');
    if contains(file, xlsx)
        fprintf("The molecular weight of Alanine is %5f\n", alaninemw);
        fprintf("The molecular weight of Arginine is %5f\n", argininemw);
        fprintf("The molecular weight of Asparigine is %5f\n", aspariginemw);
        break;
    end
end