how do I append to an array within a loop with float values?

lenArray = length(0:0.1:20);

solutions = zeros(lenArray,1);

for k=0:0.1:20

a = -k;

b = -k;

soln= a+b;

solutions(k+1)= soln;

end

Array indices must be positive integers or logical values.

Error in EXAMPLE (line 7)

solutions(k+1)= soln;

Answer 1

[Alex Sune]

Try with this:

k = 0:0.1:20;
solutions = zeros(size(k)); 
for ii = 1:numel(k)  
    a = -k(ii);
    b = -k(ii);
    soln= a+b;
    solutions(ii)= soln;
end

or without loop:

k = 0:0.1:20;
solutions = -2*k