Re: minimum real number from a list of complex numbers

[Ben Abbott]

On Oct 29, 2010, at 5:50 PM, Robert Patterson wrote:

> Hi,
> 
> I have a list of numbers (the roots of a list of quadratic equations)
> that represent the times at which two particles collide.  Some
> collisions are impossible so that times have imaginary components.  I
> want to find the lowest purely real number from the list without writing
> explicit loops.
> 
> For example from
> v=[1, 2, 2+1i, 0 + 1i]
> I want to find 1.
> 
> Does anyone have a good idea?  I cannot see how to use isreal() for this
> purpose.
> 
> Thanks
> 
> Robert

Try

        min (v(imag(v)==0))

Ben