error in calculating mid point

i have a matrix

28 45781 5 0 0 13 31 77516 7 0 0 16 37 83311 9 0 0 40

i calculated mid point but i get error not getting exact result

F_mid = conv2(K, [0.5 0.5], 'valid')

k is my above matrix

the result i get is

F_mid =

1.0e+005 *

    0.2290    0.2289    0.0000         0    0.0001
    0.3877    0.3876    0.0000         0    0.0001

please help

[Walter Roberson]

Try switching to

format long g

I think the results will make more sense

Answer 1

[Andrei Bobrov]

K = reshape([28 45781 5 0 0 13 31 77516 7 0 0 16 37 83311 9 0 0 40],6,[]).';
F_mid = conv2(K,[1 1;1 1]/4,'valid')

for you...

F_mid = conv2(K,[1;1]/2,'valid')