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Prepend a level to a pandas MultiIndex
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cs95
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answered Feb 7 '17 at 16:11
okartalokartal
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Populate data table from data reader
I'm doing a basic thing in C# (MS VS2008) and have a question more about proper design than specific code.
5 Answers
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How to print a string in fixed width?
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EDIT 2013-12-11 - This answer is very old. It is still valid and correct, but people looking at this should prefer the new format syntax.
You can use string formatting like this:
>>> print '%5s' % 'aa'
aa
>>>...
How to get overall CPU usage (e.g. 57%) on Linux [closed]
...ke a look at cat /proc/stat
grep 'cpu ' /proc/stat | awk '{usage=($2+$4)*100/($2+$4+$5)} END {print usage "%"}'
EDIT please read comments before copy-paste this or using this for any serious work. This was not tested nor used, it's an idea for people who do not want to install a utility or for so...
Capturing Groups From a Grep RegEx
I've got this little script in sh (Mac OSX 10.6) to look through an array of files. Google has stopped being helpful at this point:
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Convert JS date time to MySQL datetime
...nction to pad numbers to two digits…
**/
function twoDigits(d) {
if(0 <= d && d < 10) return "0" + d.toString();
if(-10 < d && d < 0) return "-0" + (-1*d).toString();
return d.toString();
}
/**
* …and then create the method to output the date string as ...
isset() and empty() - what to use
...mpty checks if the variable is set and if it is it checks it for null, "", 0, etc
Isset just checks if is it set, it could be anything not null
With empty, the following things are considered empty:
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a float)
"0" (0 as a string)
NULL
FALSE
array(...
Is there an expression for an infinite generator?
...gument iter = zero-argument callable + sentinel value
int() always returns 0
Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One variant of particular note is iter(f, object()),...
Fill between two vertical lines in matplotlib
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import matplotlib.pyplot as plt
fig, ax = plt.subplots()
ax.plot(range(20))
ax.axvspan(8, 14, alpha=0.5, color='red')
plt.show()
You could use fill_betweenx to do this, but the extents (both x and y) of the rectangle would be in data coordinates. With axvspan, the y-extents of the rectangle...
When to use “new” and when not to, in C++? [duplicate]
...s out of scope. Some examples of this are:
void foo()
{
Point p = Point(0,0);
} // p is now destroyed.
for (...)
{
Point p = Point(0,0);
} // p is destroyed after each loop
Some people will say that the use of new decides whether your object is on the heap or the stack, but that is only true...