class_docstr: Locations must have the base master at the origin (ie. 0).
  
  If the extrapolate argument is set to True, then values are extrapolated
  outside the axis range.
  
    >>> from pprint import pprint
    >>> locations = [       {'wght':100},       {'wght':-100},       {'wght':-180},       {'wdth':+.3},       {'wght':+120,'wdth':.3},       {'wght':+120,'wdth':.2},       {},       {'wght':+180,'wdth':.3},       {'wght':+180},       ]
    >>> model = VariationModel(locations, axisOrder=['wght'])
    >>> pprint(model.locations)
    [{},
     {'wght': -100},
     {'wght': -180},
     {'wght': 100},
     {'wght': 180},
     {'wdth': 0.3},
     {'wdth': 0.3, 'wght': 180},
     {'wdth': 0.3, 'wght': 120},
     {'wdth': 0.2, 'wght': 120}]
    >>> pprint(model.deltaWeights)
    [{},
     {0: 1.0},
     {0: 1.0},
     {0: 1.0},
     {0: 1.0},
     {0: 1.0},
     {0: 1.0, 4: 1.0, 5: 1.0},
     {0: 1.0, 3: 0.75, 4: 0.25, 5: 1.0, 6: 0.6666666666666666},
     {0: 1.0,
      3: 0.75,
      4: 0.25,
      5: 0.6666666666666667,
      6: 0.4444444444444445,
      7: 0.6666666666666667}]
code: def _locationsToRegions(self):
      locations = self.locations
      # Compute min/max across each axis, use it as total range.
      # TODO Take this as input from outside?
      minV = {}
      maxV = {}
      for l in locations:
          for k, v in l.items():
              minV[k] = min(v, minV.get(k, v))
              maxV[k] = max(v, maxV.get(k, v))
  
      regions = []
      for loc in locations:
          region = {}
          for axis, locV in loc.items():
              if locV > 0:
                  region[axis] = (0, locV, maxV[axis])
              else:
                  region[axis] = (minV[axis], locV, 0)
          regions.append(region)
      return regions
  
imports: from fontTools.misc.roundTools import noRound
  from .errors import VariationModelError
label_desc: Use image node_id 7 for calling the VariationModel obj's underlying member method code with example usage: obj._locationsToRegions() and returns: regions