[julia-users] Conditional works like on the selected columns of the matrix

[paul analyst]

I have a logical vector t 
julia> t 
1x4 BitArray{2}:
 true  false  false  false

and matrix v
julia> v 
4x4 Array {Float64, 2}: 
  -0.0018187 -0.18174 0.982684 0.0360478 
  -0.018408 0.98314 0.1819 -0.00297265 
  -0.995394 -0.0167994 -0.00839779 0.0940118 
   0.0940681 0.0111097 -0.0342677 0.994914 

How quickly multiplied by -1 only the columns where vactor t = true  ?
Paul