in the following code snippet:
import cv2 for color_space in (cv2.COLOR_RGB2HSV, cv2.COLOR_RGB2LUV, cv2.COLOR_RGB2HLS, cv2.COLOR_RGB2YUV, cv2.COLOR_RGB2YCrCb): *print_it_as_name(color_space)* With which real statement can I replace print_it_as_name such that the output is
cv2.COLOR_RGB2HSV cv2.COLOR_RGB2LUV cv2.COLOR_RGB2HLS cv2.COLOR_RGB2YUV, cv2.COLOR_RGB2YCrCb
Without hardcoding it using if statements?
As others suggested, use a dict.
import cv2 data = { 'cv2.'+att : getattr(cv2, att) for att in ('COLOR_RGB2HSV','COLOR_RGB2LUV',...) } print(data.keys()) If you need all the COLOR_* attributes, you can avoid the hard coded list:
data = { ... for att in dir(cv2) if att.startswith('COLOR_') } Use a reverse-map, mapping from the value, to its original name (assuming values are unique).
import cv2 reverse_map = { v:k for k,v in dir(cv2) if k.startswith('COLOR_') } for color_space in (cv2.COLOR_RGB2HSV, cv2.COLOR_RGB2LUV, cv2.COLOR_RGB2HLS, cv2.COLOR_RGB2YUV, cv2.COLOR_RGB2YCrCb): print(reverse_map[color_space]) Ok I've come up with a little hack to work this out using eval:
for color_space in ("cv2.COLOR_RGB2HSV", "cv2.COLOR_RGB2LUV", "cv2.COLOR_RGB2HLS", "cv2.COLOR_RGB2YUV", "cv2.COLOR_RGB2YCrCb"): print(color_space) # prints the name of the variable print(eval(color_space)) # prints the actual value of the variable. Probably not good practice to actually do this, I would recommend the dictionary approach but since you asked for it this way this is how its done.
eval, you should use getattr instead.
''? If you want to work with variables dynamically you can always use their names as strings and obtain the corresponding values viagetattr.