>> f = @(x) 5.*x-2

f =

    @(x)5.*x-2

>> a = randn(6)

a =

    1.2607    0.0230    0.6252    0.5152    1.6821   -0.2741
    0.6601    0.0513    0.1832    0.2614   -0.8757    1.5301
   -0.0679    0.8261   -1.0298   -0.9415   -0.4838   -0.2490
   -0.1952    1.5270    0.9492   -0.1623   -0.7120   -1.0642
   -0.2176    0.4669    0.3071   -0.1461   -1.1742    1.6035
   -0.3031   -0.2097    0.1352   -0.5320   -0.1922    1.2347

>> a = a * (a>10)

ans =

   12.6066    5.1525         0         0   12.6066   14.3108
    6.6014    2.6141         0         0    6.6014    7.0563
   -0.6787   -9.4149         0         0   -0.6787    0.9322
   -1.9522   -1.6234         0         0   -1.9522   -2.4924
   -2.1761   -1.4605         0         0   -2.1761    8.9616
   -3.0311   -5.3201         0         0   -3.0311    8.3273

>> f(ans)

ans =

   61.0329   -2.0000   -2.0000   -2.0000   82.1052   -2.0000
   -2.0000   -2.0000   -2.0000   -2.0000   -2.0000   74.5036
   -2.0000   -2.0000   -2.0000   -2.0000   -2.0000   -2.0000
   -2.0000   74.3488   -2.0000   -2.0000   -2.0000   -2.0000
   -2.0000   -2.0000   -2.0000   -2.0000   -2.0000   78.1729
   -2.0000   -2.0000   -2.0000   -2.0000   -2.0000   59.7340

>> ans .* (ans > 0)

ans =

   61.0329         0         0         0   82.1052         0
         0         0         0         0         0   74.5036
         0         0         0         0         0         0
         0   74.3488         0         0         0         0
         0         0         0         0         0   78.1729
         0         0         0         0         0   59.7340