class_docstr: Class for fitting the Diffusion Kurtosis Microstructural Model 
class_docstr_tok: ["Class","for","fitting","the","Diffusion","Kurtosis","Microstructural","Model"]
docstr: To raise error if only the axonal water fraction was computed 
docstr_tok: ["To","raise","error","if","only","the","axonal","water","fraction","was","computed"]
code: def _is_awfonly(self):
      """To raise error if only the axonal water fraction was computed"""
      if self.model_params.shape[-1] < 39:
          raise ValueError(
              "Only the awf was processed! Rerun model fit "
              "with input parameter awf_only set to False"
          )
  
imports: import numpy
  from dipy.reconst.dti import lower_triangular, from_lower_triangular, decompose_tensor, trace, mean_diffusivity, radial_diffusivity, axial_diffusivity, MIN_POSITIVE_SIGNAL
  from dipy.reconst.dki import split_dki_param, _positive_evals, directional_kurtosis, directional_diffusion, kurtosis_maximum, DiffusionKurtosisModel, DiffusionKurtosisFit
  from dipy.reconst.dti import design_matrix
  from dipy.core.ndindex import ndindex
  from dipy.reconst.vec_val_sum import vec_val_vect
  from dipy.data import get_sphere
  import dipy.core.sphere
label_desc: Use image node_id 9 for calling the KurtosisMicrostructuralFit obj's underlying member method code with example usage: obj._is_awfonly() without return types