code: def rt_err_estimate(arr_t, out_dtype, slope, inter):
      # Error attributable to rounding
      slope = 1 if slope is None else slope
      inter = 1 if inter is None else inter
      max_int_miss = slope / 2.0
      # Estimate error attributable to floating point slope / inter;
      # Remove inter / slope, put in a float type to simulate the type
      # promotion for the multiplication, apply slope / inter
      flt_there = (arr_t - inter) / slope
      flt_back = flt_there.astype(out_dtype) * slope + inter
      max_flt_miss = np.abs(arr_t - flt_back).max()
      # Max error is sum of rounding and fp error
      return max_int_miss + max_flt_miss
  
imports: import itertools
  from io import BytesIO
  from platform import machine, python_compiler
  import numpy
  import pytest
  from numpy.testing import assert_array_almost_equal, assert_array_equal
  from ..arraywriters import ArrayWriter, ScalingError, SlopeArrayWriter, SlopeInterArrayWriter, WriterError, get_slope_inter, make_array_writer
  from ..casting import int_abs, sctypes, shared_range, type_info
  from ..testing import assert_allclose_safely, suppress_warnings
  from ..volumeutils import _dt_min_max, apply_read_scaling, array_from_file
label_desc: Use image node_id 25 for calling a global function with example usage: rt_err_estimate(arr_t, out_dtype, slope, inter) and returns: unknown