class_docstr: normalize values at `index`
code: def transform(self, t):
      # create a view of t and modify that.  Modifying t directly doesn't
      # work for some reason ...
      tr = t.reshape((3, -1))
      tr[:] = (tr - self.xmin) / self.xspan * self.yspan + self.ymin
      return t
  
imports: from __future__ import division
  import numpy
  from neon import NervanaObject
label_desc: Use image node_id 2 for calling the ValueNormalize obj's underlying member method code with example usage: obj.transform(t) and returns: t