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Counting the Number of keywords in a dictionary in python
...oops through the data and pass the values to countoccurrences function
if __name__ == "__main__":
store = {}
list = ('a', 'a', 'b', 'c', 'c')
for data in list:
countoccurrences(store, data)
for k, v in store.iteritems():
print "Key " + k + " has occurred " + str(v) ...
Weak and strong property setter attributes in Objective-C
...n release autorelease etc... Instead you use strong weak for properties or __strong
__weak
for variables (defaults to __strong). Strong is the equivalent to retain, however ARC will manage the release for you.
The only time you would want to use weak, is if you wanted to avoid retain cycles (e.g...
Why do you have to call .items() when iterating over a dictionary in Python?
...te over the same items. Implementation-wise they are different operations (__contains__ vs. __iter__). But that little inconsistency would be somewhat confusing and, well, inconsistent.
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Is there any Rails function to check if a partial exists?
...
Currently, I'm using the following in my Rails 3/3.1 projects:
lookup_context.find_all('posts/_form').any?
The advantage over other solutions I've seen is that this will look in all view paths instead of just your rails root. This is important to me as I have a lot of rails engines.
This a...
Double Negation in C++
...ernel). For GCC, they're implemented as follows:
#define likely(cond) (__builtin_expect(!!(cond), 1))
#define unlikely(cond) (__builtin_expect(!!(cond), 0))
Why do they have to do this? GCC's __builtin_expect treats its parameters as long and not bool, so there needs to be some form of conver...
Python matplotlib multiple bars
...n='center')
ax.bar(x+0.2, k, width=0.2, color='r', align='center')
ax.xaxis_date()
plt.show()
I don't know what's the "y values are also overlapping" means, does the following code solve your problem?
ax = plt.subplot(111)
w = 0.3
ax.bar(x-w, y, width=w, color='b', align='center')
ax.bar(x, z,...
“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
...y 4 bytes in UTF-8.
You may also have to set the server property character_set_server to utf8mb4 in the MySQL configuration file. It seems that Connector/J defaults to 3-byte Unicode otherwise:
For example, to use 4-byte UTF-8 character sets with Connector/J, configure the MySQL server with cha...
Find out whether Chrome console is open
...id
var checkStatus;
var element = document.createElement('any');
element.__defineGetter__('id', function() {
checkStatus = 'on';
});
setInterval(function() {
checkStatus = 'off';
console.log(element);
console.clear();
}, 1000);
Another version (from comments)
var element = new ...
Add a column with a default value to an existing table in SQL Server
...TABLENAME}
ADD {COLUMNNAME} {TYPE} {NULL|NOT NULL}
CONSTRAINT {CONSTRAINT_NAME} DEFAULT {DEFAULT_VALUE}
WITH VALUES
Example:
ALTER TABLE SomeTable
ADD SomeCol Bit NULL --Or NOT NULL.
CONSTRAINT D_SomeTable_SomeCol --When Omitted a Default-Constraint Name is autogenerated.
DEFAULT (...
Rails 3 execute custom sql query without a model
...
Maybe try this:
ActiveRecord::Base.establish_connection(...)
ActiveRecord::Base.connection.execute(...)
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