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Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
I have a data frame df and I use several columns from it to groupby :
7 Answers
7
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How do I get Month and Date of JavaScript in 2 digit format?
When we call getMonth() and getDate() on date object, we will get the single digit number .
For example :
28 Answers...
How can I perform a culture-sensitive “starts-with” operation from the middle of a string?
...
I'll consider the problem of many<->one/many casemappings first and separately from handling different Normalization forms.
For example:
x heiße y
^--- cursor
Matches heisse but then moves cursor 1 too much. And:
x heisse y
^--- cursor
Matches heiße but then moves cursor 1 to...
Remove empty elements from an array in Javascript
...that are falsy, which include an empty string "", 0, NaN, null, undefined, and false.
You can pass to the filter method, the Boolean constructor function, or return the same element in the filter criteria function, for example:
var filtered = array.filter(Boolean);
Or
var filtered = array.filte...
How to format a number as percentage in R?
...scales package, as documented in krlmlr's answer. Use that instead of my hand-rolled solution.
Try something like
percent <- function(x, digits = 2, format = "f", ...) {
paste0(formatC(100 * x, format = format, digits = digits, ...), "%")
}
With usage, e.g.,
x <- c(-1, 0, 0.1, 0.5555...
How do you add swap to an EC2 instance?
I'm currently running an ec2 micro instance and i've been finding that the instance occasionally runs out of memory.
10 Ans...
How to debug Lock wait timeout exceeded on MySQL?
...nnoDB tables.
Since you know the query, all the tables being accessed are candidates for being the culprit.
From there, you should be able to run SHOW ENGINE INNODB STATUS\G
You should be able to see the affected table(s)
You get all kinds of additional Locking and Mutex Information.
Here is a sampl...
Remove outline from select box in FF
...0,0,0);
text-shadow: 0 0 0 #000;
}
We put a text shadow with no offset and no blur, so that replaces the text. Of course older browser don't understand anything of this, so we must provide a fallback for the color:
select {
color: #000;
color: rgba(0,0,0,0);
text-shadow: 0 0 0 #000;
}
T...
Understanding how recursive functions work
...grok yet. Filtering out all of the (extremely clever) "In order to understand recursion, you must first understand recursion." replies from various online threads I still am not quite getting it.
...
How does this CSS produce a circle?
...f 180 pixels?
Let's reformulate that into two questions:
Where do width and height actually apply?
Let's have a look at the areas of a typical box (source):
The height and width apply only on content, if the correct box model is being used (no quirks mode, no old Internet Explorer).
Where d...