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Python: Checking if a 'Dictionary' is empty doesn't seem to work
...sing the first way only though. The other two ways are way too wordy.
test_dict = {}
if not test_dict:
print "Dict is Empty"
if not bool(test_dict):
print "Dict is Empty"
if len(test_dict) == 0:
print "Dict is Empty"
...
How to atomically delete keys matching a pattern using Redis
In my Redis DB I have a number of prefix:<numeric_id> hashes.
23 Answers
23
...
Simple Digit Recognition OCR in OpenCV-Python
...e KNearest for simple OCR purposes).
1) My first question was about letter_recognition.data file that comes with OpenCV samples. I wanted to know what is inside that file.
It contains a letter, along with 16 features of that letter.
And this SOF helped me to find it. These 16 features are explain...
List of foreign keys and the tables they reference
...
The referenced primary key is described in the columns r_owner and r_constraint_name of the table ALL_CONSTRAINTS. This will give you the info you want:
SELECT a.table_name, a.column_name, a.constraint_name, c.owner,
-- referenced pk
c.r_owner, c_pk.table_name r_ta...
multiple prints on the same line in Python
... can use the print statement to do this without importing sys.
def install_xxx():
print "Installing XXX... ",
install_xxx()
print "[DONE]"
The comma on the end of the print line prevents print from issuing a new line (you should note that there will be an extra space at the end of the ou...
A transport-level error has occurred when receiving results from the server [closed]
... This one is the actual answer.
– TheHuge_
Nov 14 '16 at 16:55
2
In my particular cas...
What are the rules for the “…” token in the context of variadic templates?
...rgs...) above!
You can use ... to initialize an array also as:
struct data_info
{
boost::any data;
std::size_t type_size;
};
std::vector<data_info> v{{args, sizeof(T)}...}; //pattern = {args, sizeof(T)}
which is expanded to this:
std::vector<data_info> v
{
{arg0, sizeo...
Python: split a list based on a condition?
...ike: [ ('file1.jpg', 33L, '.jpg'), ('file2.avi', 999L, '.avi'), ... ]
IMAGE_TYPES = ('.jpg','.jpeg','.gif','.bmp','.png')
images = [f for f in files if f[2].lower() in IMAGE_TYPES]
anims = [f for f in files if f[2].lower() not in IMAGE_TYPES]
Again, this is fine!
There might be slight performanc...
Constructor initialization-list evaluation order
...ped aborting. This is an example of the syntax I'm using. The thing is, a_ needs to be initialized before b_ in this case. Can you guarantee the order of construction?
...
What does O(log n) mean exactly?
...) definition which finally makes sense. +1
– iAteABug_And_iLiked_it
Aug 30 '13 at 17:19
...