Mathematical Operations on Array

[Bryan.Fodness@gmail.com]

I am loading text into an array and would like to convert the values.

from math import *
from numpy import *
from pylab import *

data=loadtxt('raw.dat')
mincos=degrees(acos(data[:,0]))
minazi=degrees(data[:,1])
minthick=data[:,2]/0.006858

I am not sure why degrees()  works, but acos() does not.

I receive the following

Traceback (most recent call last):
  File "C:\ test.py", line 6, in ?
    mincos=degrees(acos(float(data[:,0])))
TypeError: only length-1 arrays can be converted to Python scalars

Can anyone tell me what I am doing wrong?