python函数的绝对导入

Question

trend.py and test_trend.py are in the same folder. I have a class Trend with a function find_regres_values that is called from a instance method perform_analysis.

trend.py:

class Trend:
    def __init__(self, values, trend_type):
        self.all_values = values

    def permorn_analysis(self, first, trend_type):
        #blabla
        vals_reg = ["a", "b", "c", "d"]
        find_regres_values(vals_reg, first, trend_type)

    def find_regres_values(vals_reg, first, trend_type):
        #do somethin
        pass

in test_trend.py

from trend import find_regres_values
class ConsecRegions(unittest.TestCase):

    def test_find_regres_values_decreas_min_before_max(self):
        #initialize some values
        output = find_regres_values(vals_reg, first, trend_type)
        self.assertEqual(output, result)

It shows me an error:

  File "test_trend.py", line 2, in <module>
    from trend import find_regres_values
ImportError: cannot import name find_regres_values

How do I import one function for testing?

Answer 1

find_regres_values is a method of the class Trend , If you want find_regres_values to be its own function then remove the indentation

class Trend:
    def __init__(self, values, trend_type):
        self.all_values = values
    def permorn_analysis(self,first,trend_type)
        #blabla
        vals_reg = some list
        find_regres_values(vals_reg, first, trend_type)

def find_regres_values(vals_reg, first, trend_type):
    #do something

Answer 2

What Python version you use?

If Python 3.x:

Create empty file __init__.py

For correct import use this code:

from trend import Trend

and edit call of method:

from trend import Trend

class ConsecRegions(unittest.TestCase):

    def test_find_regres_values_decreas_min_before_max(self):
        #initialize some values
        output = Trend.find_regres_values(vals_reg, first, trend_type)
        self.assertEqual(output, result)

For information:

In file trend.py after permorn_analysis method insert a colon.