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Parse (split) a string in C++ using string delimiter (standard C++)
...>=tiger";
std::string delimiter = ">=";
std::string token = s.substr(0, s.find(delimiter)); // token is "scott"
The find(const string& str, size_t pos = 0) function returns the position of the first occurrence of str in the string, or npos if the string is not found.
The substr(size_t p...
Hex representation of a color with alpha channel?
...se rgba() functional notation with decimals or percentages, e.g. rgba(255, 0, 0, 0.5) would be 50% transparent red. RGB channels are 0-255 or 0%-100%, alpha is 0-1.
In CSS 4*, you can specify the alpha channel using the 7th and 8th characters of an 8 digit hex colour, or 4th character of a 4 digit ...
On localhost, how do I pick a free port number?
...do I figure out which port is available? I assume I cannot listen on port 80 or 21?
5 Answers
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Best way to test if a row exists in a MySQL table
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edited Sep 4 '19 at 19:20
SovietFrontier
1,5441010 silver badges2727 bronze badges
answered Nov 4 '09 ...
What is the Difference Between read() and recv() , and Between send() and write()?
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The difference is that recv()/send() work only on socket descriptors and let you specify certain...
MySQL - Rows to Columns
...temvalue |
+--------+----------+-----------+
| 1 | A | 10 |
| 1 | B | 3 |
| 2 | A | 9 |
| 2 | C | 40 |
+--------+----------+-----------+
This will be our goal, the pretty pivot table:
select * from history_itemvalue_piv...
How to access pandas groupby dataframe by key
...group method:
In [21]: gb.get_group('foo')
Out[21]:
A B C
0 foo 1.624345 5
2 foo -0.528172 11
4 foo 0.865408 14
Note: This doesn't require creating an intermediary dictionary / copy of every subdataframe for every group, so will be much more memory-efficient that creating...
Shuffle two list at once with same order
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– Jaroslav Klimčík
Apr 25 '14 at 10:15
4
(noob question) - what does the * mean?
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How do I get my Python program to sleep for 50 milliseconds?
How do I get my Python program to sleep for 50 milliseconds?
6 Answers
6
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Join a list of strings in python and wrap each string in quotation marks
...ords = ['hello', 'world', 'you', 'look', 'nice']
>>> ', '.join('"{0}"'.format(w) for w in words)
'"hello", "world", "you", "look", "nice"'
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