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Modifying the “Path to executable” of a windows service
... answered Jul 22 '14 at 0:33
Niall ConnaughtonNiall Connaughton
13.5k1010 gold badges4848 silver badges4646 bronze badges
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Converting strings to floats in a DataFrame
...newer version of pandas (0.17 and up), you can use to_numeric function. It allows you to convert the whole dataframe or just individual columns. It also gives you an ability to select how to treat stuff that can't be converted to numeric values:
import pandas as pd
s = pd.Series(['1.0', '2', -3])
p...
How to query MongoDB with “like”?
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Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what'...
Why does sudo change the PATH?
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Yeah, but it's totally counterintuitive. It probably fools the good guys more than the bad guys.
– Brian Armstrong
Jun 20 '09 at 2:24
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How to convert JSON string to array
...d keys). That's what the documentation says and that's what my PHP 5.2 installation returns. Are you using a function other than the official, built-in json_decode()? What does var_dump(json_decode($str, true)); return?
– RickN
Sep 22 '11 at 15:34
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When to use EntityManager.find() vs EntityManager.getReference() with JPA
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I usually use getReference method when i do not need to access database state (I mean getter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful featu...
How to initialize a vector in C++ [duplicate]
...p;arr[0]+N; }
And then you can do this without having to repeat the size all over:
int vv[] = { 12,43 };
std::vector<int> v(begin(vv), end(vv));
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Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
How do I remove all specific characters at the end of a string in PHP?
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using rtrim replaces all "." at the end, not just the last character
$string = "something here..";
echo preg_replace("/\.$/","",$string);
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Random number generation in C++11: how to generate, how does it work? [closed]
...ad about it (what is that engine , maths term like distribution , "where all integers produced are equally likely ").
2...