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HTTP error 403 in Python 3 Web Scraping
...ily detected). Try setting a known browser user agent with:
from urllib.request import Request, urlopen
req = Request('http://www.cmegroup.com/trading/products/#sortField=oi&sortAsc=false&venues=3&page=1&cleared=1&group=1', headers={'User-Agent': 'Mozilla/5.0'})
webpage = urlop...
Storing time-series data, relational or non?
...ta"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a 16 billion row table is instantaneous).
Your table has one serio...
How to extract a floating number from a string [duplicate]
...ng stuff in the following answer of mine that I did for a previous similar question:
https://stackoverflow.com/q/5929469/551449
In this answer, I proposed a pattern that allows a regex to catch any kind of number and since I have nothing else to add to it, I think it is fairly complete
...
MFC CString::Format()函数详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...殊意义，比如"%6s"
格式指令具有以下的形式：
"%" [index ":"] ["-"] [width] ["." prec] type
它是以"%"开始,而以type结束，type表示一个具体的类型。中间是用来格式化type类型的指令字符，是可选的。
先来看看type,type可以是以下...
How do I get the base URL with PHP?
...Try this:
<?php echo "http://" . $_SERVER['SERVER_NAME'] . $_SERVER['REQUEST_URI']; ?>
Learn more about the $_SERVER predefined variable.
If you plan on using https, you can use this:
function url(){
return sprintf(
"%s://%s%s",
isset($_SERVER['HTTPS']) && $_SERVER['HTTP...
Why should I use a pointer rather than the object itself?
...st shows how many bad C++ programmers there are.
In a sense, you have two questions bundled up into one. The first is when should we use dynamic allocation (using new)? The second is when should we use pointers?
The important take-home message is that you should always use the appropriate tool for...
Checking whether a variable is an integer or not [duplicate]
... check this.
Example (to do something every xth time in a for loop):
for index in range(y):
# do something
if (index/x.).is_integer():
# do something special
Edit:
You can always convert to a float before calling this method. The three possibilities:
>>> float(5).is_i...
Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...CALC_FOUND_ROWS?
Just a quick summary: Peter says that it depends on your indexes and other factors. Many of the comments to the post seem to say that SQL_CALC_FOUND_ROWS is almost always slower - sometimes up to 10x slower - than running two queries.
...
When should I use the HashSet type?
...id Clear();
bool Contains(T item);
void CopyTo(T[] array, int arrayIndex);
bool Remove(T item);
// Properties
int Count { get; }
bool IsReadOnly { get; }
}
A List<T> implements IList<T>, which extends the ICollection<T>
public interface IList<T> : IC...
Hash Map in Python
... self.store = [None for _ in range(16)]
def get(self, key):
index = hash(key) & 15
if self.store[index] is None:
return None
n = self.store[index]
while True:
if n.key == key:
return n.value
else:
...