I have some interface class, if numpy is available I would provide some extra method for the class (faster implementation)
It is possible to define some function based on the success of an import, but the same code does not work for class methods.
This code
try:
import numpy
def main2():
ret_array= numpy.array([],dtype=numpy.double)
return ret_array
except ImportError:
def main2():
print ("do nothing")
successfully defines a main2() which returns an empty numpy array
But this code
class xxx:
try:
import numpy
def main2():
ret_array= numpy.array([],dtype=numpy.double)
return ret_array
except ImportError:
def main2():
print ("do nothing")
results in an exception
if I try to call main2()
xxx.main2()
Traceback (most recent call last):
File "<interactive input>", line 1, in <module>
File "test2.py", line 17, in main2
ret_array= numpy.array([],dtype=numpy.double)
NameError: name 'numpy' is not defined
Is there some other way to achieve this? (based on the availability of a module define a class method differently)
try:
import numpy
class xxx:
def main2(self):
ret_array = numpy.array([],dtype=numpy.double)
print(ret_array)
except:
class xxx:
def main2(self):
print("do nothing")
You could try:
class Test:
def test(self):
try:
import numpy
import_succeeded = True
except:
import_succeeded = False
if import_succeeded:
pass
else:
pass
Thanks for all the hints I received
the solution I'm going to use is:
try:
import numpy
except ImportError:
numpy = None
class xxx:
if numpy:
def main2():
ret_array= numpy.array([],dtype=numpy.double)
return ret_array
else:
def main2():
print ("do nothing")