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How do I convert from int to String?
... String.valueOf(i).
The concatenation will work, but it is unconventional and could be a bad smell as it suggests the author doesn't know about the two methods above (what else might they not know?).
Java has special support for the + operator when used with strings (see the documentation) which t...
What characters are allowed in an email address?
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See RFC 5322: Internet Message Format and, to a lesser extent, RFC 5321: Simple Mail Transfer Protocol.
RFC 822 also covers email addresses, but it deals mostly with its structure:
addr-spec = local-part "@" domain ; global address
local-part ...
How does one reorder columns in a data frame?
...mns like so df[,c(1,2,3,4)].
Note the first comma means keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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How to reload a page using JavaScript
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what is the difference between location.reload() and window.location.reload() ?
– Raptor
Dec 20 '13 at 4:29
58
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How to convert SQL Query result to PANDAS Data Structure?
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Here's the shortest code that will do the job:
from pandas import DataFrame
df = DataFrame(resoverall.fetchall())
df.columns = resoverall.keys()
You can go fancier and parse the types as in Paul's answer.
...
Determine the number of lines within a text file
...m all into an array like ReadAllLines. So now you can have both efficiency and conciseness with:
var lineCount = File.ReadLines(@"C:\file.txt").Count();
Original Answer
If you're not too bothered about efficiency, you can simply write:
var lineCount = File.ReadAllLines(@"C:\file.txt").Length;...
Convert floats to ints in Pandas?
I've been working with data imported from a CSV. Pandas changed some columns to float, so now the numbers in these columns get displayed as floating points! However, I need them to be displayed as integers, or, without comma. Is there a way to convert them to integers or not display the comma?
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pandas: filter rows of DataFrame with operator chaining
Most operations in pandas can be accomplished with operator chaining ( groupby , aggregate , apply , etc), but the only way I've found to filter rows is via normal bracket indexing
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Web API Put Request generates an Http 405 Method Not Allowed error
...ws Features to make sure I didn't have this thing called WebDAV installed, and it said I didn't. Anyways, I went ahead and placed the following in my web.config (both front end and WebAPI, just to be sure), and it works now. I placed this inside <system.webServer>.
<modules runAllManaged...
Can I call a constructor from another constructor (do constructor chaining) in C++?
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C++11: Yes!
C++11 and onwards has this same feature (called delegating constructors).
The syntax is slightly different from C#:
class Foo {
public:
Foo(char x, int y) {}
Foo(int y) : Foo('a', y) {}
};
C++03: No
Unfortunately, there'...