Print real roots only in numpy

Question

I have something like this:

coefs = [28, -36, 50, -22]
print(numpy.roots(coefs))

Of course the result is:

[ 0.35770550+1.117926         


        

Answer 1

You can do it, using iscomplex as follows:

r = numpy.roots(coefs)

In [15]: r[~numpy.iscomplex(r)]
Out[15]: array([ 0.57030329+0.j])

Also you can use isreal as pointed out in comments:

In [17]: r[numpy.isreal(r)]
Out[17]: array([ 0.57030329+0.j])