docs: def convert(isoel, col1, col2,
                  channel_width_in, channel_width_out,
                  flow_rate_in, flow_rate_out,
                  viscosity_in, viscosity_out,
                  inplace=False):
          """Convert isoelastics in area_um-deform space
  
          Parameters
          ----------
          isoel: list of 2d ndarrays of shape (N, 3)
              Each item in the list corresponds to one isoelasticity
              line. The first column is defined by `col1`, the second
              by `col2`, and the third column is the emodulus.
          col1, col2: str
              Define the fist to columns of each isoelasticity line.
              One of ["area_um", "circ", "deform"]
          channel_width_in: float
              Original channel width [µm]
          channel_width_out: float
              Target channel width [µm]
          flow_rate_in: float
              Original flow rate [µl/s]
          flow_rate_in: float
              Target flow rate [µl/s]
          viscosity_in: float
              Original viscosity [mPa*s]
          viscosity_out: float
              Target viscosity [mPa*s]
  
          Notes
          -----
          If only the positions of the isoelastics are of interest and
          not the value of the elastic modulus, then it is sufficient
          to supply values for the channel width and set the values
          for flow rate and viscosity to a constant (e.g. 1).
  
          See Also
          --------
          dclab.features.emodulus.convert: conversion method used
          """
          Isoelastics.check_col12(col1, col2)
          if col1 == "area_um":
              area_ax = 0
              defo_ax = 1
          else:
              area_ax = 1
              defo_ax = 0
  
          new_isoel = []
  
          for iso in isoel:
              iso = np.array(iso, copy=not inplace)
              feat_emod.convert(area_um=iso[:, area_ax],
                                deform=iso[:, defo_ax],
                                emodulus=iso[:, 2],
                                channel_width_in=channel_width_in,
                                channel_width_out=channel_width_out,
                                flow_rate_in=flow_rate_in,
                                flow_rate_out=flow_rate_out,
                                viscosity_in=viscosity_in,
                                viscosity_out=viscosity_out,
                                inplace=True)
              new_isoel.append(iso)
          return new_isoel