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Pandas - Get first row value of a given column
...ime'] = x does not work:
In contrast, assignment with df.iloc[0]['bar'] = 123 does not work because df.iloc[0] is returning a copy:
In [66]: df.iloc[0]['bar'] = 123
/home/unutbu/data/binky/bin/ipython:1: SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame
Se...
Renaming a virtualenv folder without breaking it
... using and so don't encounter the problem.
– CoderGuy123
Nov 4 '16 at 18:06
Scratch that! Today I ran into a problem: ...
Why is it slower to iterate over a small string than a small list?
...rule out Tim Peter's 10-times-upvoted answer!
>>> foo = iterable[123]
>>> iterable[36] is foo
True
These are not new objects!
But this is worth mentioning: indexing costs. The difference will likely be in the indexing, so remove the iteration and just index:
>>> pytho...
MySQL join with where clause
... in A table which having id null in B table
– Veeresh123
Aug 29 '16 at 6:57
@Veeresh123, what are A and B table ? Can ...
Using generic std::function objects with member functions in one class
...;
// Call with late supplied 'this'
MyClass myInst;
callable(&myInst, 123);
What would the storage type look like without auto?
Something like this:
std::_Mem_fn_wrap<void,void (__cdecl TestA::*)(int),TestA,int> callable
You can also pass this function storage to a standard function ...
how to change default python version?
...in 8 Apr 28 15:51 pydoc3@ -> pydoc3.2
-rwxrwxr-x 1 root admin 123 Feb 20 11:14 pydoc3.2*
-rwxrwxr-x 2 root admin 25624 Feb 20 11:14 python3*
lrwxr-xr-x 1 root admin 12 Apr 28 15:51 python3-32@ -> python3.2-32
lrwxr-xr-x 1 root admin 16 Apr 28 15:51 python3-config@ ->...
Show hidden div on ng-click within ng-repeat
...hide the first div when I click on second div.
– User123
Oct 12 '16 at 7:41
To answer the Q above... Just change the n...
Typedef function pointer?
... {
return u*v;
}
t_somefunc afunc = &product;
...
int x2 = (*afunc)(123, 456); // call product() to calculate 123*456
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...们 发布日志 服务条款 教育 入门必读 中文教程 IoT专题 AI2拓展 ChatGPT接入 Aia Store 开通VIP 搜索 ...
Javascript seconds to minutes and seconds
... var secs = ~~duration % 60;
// Output like "1:01" or "4:03:59" or "123:03:59"
var ret = "";
if (hrs > 0) {
ret += "" + hrs + ":" + (mins < 10 ? "0" : "");
}
ret += "" + mins + ":" + (secs < 10 ? "0" : "");
ret += "" + secs;
return ret;
}
~~ is a sh...