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How to convert list of tuples to multiple lists?
...
xs, ys = [x for x, y in zs], [y for x, y in zs]
return xs, ys
if __name__ == '__main__':
from timeit import timeit
setup_string='''\
N = 2000000
xs = list(range(1, N))
ys = list(range(N+1, N*2))
zs = list(zip(xs, ys))
from __main__ import t1, t2, t3
'''
print(f'zip:\t\t{timeit(...
Display names of all constraints for a table in Oracle SQL
...
You need to query the data dictionary, specifically the USER_CONS_COLUMNS view to see the table columns and corresponding constraints:
SELECT *
FROM user_cons_columns
WHERE table_name = '<your table name>';
FYI, unless you specifically created your table with ...
How to get the system uptime in Windows? [closed]
...and line utility checks and displays various system statistics such as installation date, installed hotfixes and more.
Open a Command Prompt and type the following command:
systeminfo
You can also narrow down the results to just the line you need:
systeminfo | find "System Boot Time:"
3: By ...
How do you remove duplicates from a list whilst preserving order?
...n seen or seen_add(x))]
Why assign seen.add to seen_add instead of just calling seen.add? Python is a dynamic language, and resolving seen.add each iteration is more costly than resolving a local variable. seen.add could have changed between iterations, and the runtime isn't smart enough to rule t...
Reading binary file and looping over each byte
...hile byte != "":
# Do stuff with byte.
byte = f.read(1)
finally:
f.close()
Python 2.5-2.7
with open("myfile", "rb") as f:
byte = f.read(1)
while byte != "":
# Do stuff with byte.
byte = f.read(1)
Note that the with statement is not available in versio...
Is it possible to use getters/setters in interface definition?
At the moment, TypeScript does not allow use get/set methods(accessors) in interfaces.
For example:
4 Answers
...
Find intersection of two nested lists?
... 3 filter returns an iterable instead of list, so you need to wrap filter calls with list():
c3 = [list(filter(lambda x: x in c1, sublist)) for sublist in c2]
Explanation:
The filter part takes each sublist's item and checks to see if it is in the source list c1.
The list comprehension is exec...
How to Create Multiple Where Clause Query Using Laravel Eloquent?
... '<>', 'value_2'],
[COLUMN, OPERATOR, VALUE],
...
])
Personally I haven't found use-case for this over just multiple where calls, but fact is you can use it.
Since June 2014 you can pass an array to where
As long as you want all the wheres use and operator, you can group them this ...
jsoncpp 不能处理__int64(long long)类型数据 - C/C++ - 清泛网 - 专注C/C++及内核技术
jsoncpp 不能处理__int64(long long)类型数据jsoncpp，是一个c++的解析和生成json的开源工具。如果你的c++程序需要解析或生成json，它会使这个过程变得很简单！但是，今天在用jsoncpp进...jsoncpp，是一个c++的解析和生成json的开源工具。如...
MongoDB仿关系型数据库Group聚合例子 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...数据
Dictionary dic = new Dictionary();
dic["_userName"] = ""; // 与原字段名区分开
dic["_date"] = "";
dic["_data"] = "0";
MongoServer server = new MongoClient(MongoConnStr).GetServer();
MongoDatabase db = serve...