大约有 45,000 项符合查询结果（耗时：0.0222秒） [XML]
Why use String.Format? [duplicate]
...ing s = string.Format("Hey, {0} it is the {1}st day of {2}. I feel {3}!", _name, _day, _month, _feeling);
vs:
string s = "Hey," + _name + " it is the " + _day + "st day of " + _month + ". I feel " + feeling + "!";
Format Specifiers
(and this includes the fact you can write custom formatters)
...
How is a CRC32 checksum calculated?
... 1100001010 = Quotient (nobody cares about the quotient)
_______________
10011 ) 11010110110000 = Augmented message (1101011011 + 0000)
=Poly 10011,,.,,....
-----,,.,,....
10011,.,,....
10011,.,,....
-----,.,,....
00001.,,....
...
Serializing object that contains cyclic object value
... if (typeof v =='object') {
if ( !seen.indexOf(v) ) { return '__cycle__'; }
seen.push(v);
} return v;
});
return jso;
};
var obj={
g:{
d:[2,5],
j:2
},
e:10
};
obj.someloopshere = [
obj.g,
obj,
{ a: [ obj.e, obj ] }
];
c...
How to execute a Python script from the Django shell?
...es, it's a good idea to set it up as a custom command ie
$ ./manage.py my_command
to do this create a file in a subdir of management and commands of your app, ie
my_app/
__init__.py
models.py
management/
__init__.py
commands/
__init__.py
my_co...
Nested defaultdict of defaultdict
...
For an arbitrary number of levels:
def rec_dd():
return defaultdict(rec_dd)
>>> x = rec_dd()
>>> x['a']['b']['c']['d']
defaultdict(<function rec_dd at 0x7f0dcef81500>, {})
>>> print json.dumps(x)
{"a": {"b": {"c": {"d": {}}}}}
...
python exception message capturing
...is no longer supported in python 3. Use the following instead.
try:
do_something()
except BaseException as e:
logger.error('Failed to do something: ' + str(e))
share
|
improve this answer
...
Downloading Java JDK on Linux via wget is shown license page instead
...e.com/otn-pub/java/jdk/14.0.1+7/664493ef4a6946b186ff29eb326336a2/jdk-14.0.1_linux-x64_bin.rpm -O ~/Downloads/jdk-14.0.1_linux-x64_bin.rpm
PS: Alf added this ( me ) :-) this, I couldn't figured out how to just commented at the end... Enjoy it.
UPDATED FOR Oracle JDK 11
wget --no-check-certificate -c...
How to log source file name and line number in Python
...='%Y-%m-%d:%H:%M:%S',
level=logging.DEBUG)
logger = logging.getLogger(__name__)
logger.debug("This is a debug log")
logger.info("This is an info log")
logger.critical("This is critical")
logger.error("An error occurred")
Generates this output:
2017-06-06:17:07:02,158 DEBUG [log.py:11] Thi...
How do you create nested dict in Python?
...he following:
d = {} # can use defaultdict(dict) instead
for row in file_map:
# derive row key from something
# when using defaultdict, we can skip the next step creating a dictionary on row_key
d[row_key] = {}
for idx, col in enumerate(row):
d[row_key][idx] = col
Ac...
What is the single most influential book every programmer should read? [closed]
... For Computer Scientists http://ecx.images-amazon.com/images/I/51HCJ5R42KL._SL500_BO2,204,203,200_AA219_PIsitb-sticker-dp-arrow,TopRight,-24,-23_SH20_OU02_.jpg
Discrete Mathematics For Computer Scientists by J.K. Truss.
While this doesn't teach you programming, it teaches you fundamental mathemati...