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Dynamically select data frame columns using $ and a character value
... be matched, not evaluated.
*/
Second argument? What?! You have to realise that $, like everything else in R, (including for instance ( , + , ^ etc) is a function, that takes arguments and is evaluated. df$V1 could be rewritten as
`$`(df , V1)
or indeed
`$`(df , "V1")
But...
`$`(df , past...
release Selenium chromedriver.exe from memory
...medriver.exe from memory (I'm on Windows 7). However after each run there is one chromedriver.exe instance remain in the memory. I hope there is a way I can write something in python to kill the chromedriver.exe process. Obviously browser.close() doesn't do the work. Thanks.
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View HTTP headers in Google Chrome?
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edited Jan 5 '17 at 19:20
Jeff Atwood
59.7k4545 go...
how to compare two elements in jquery [duplicate]
...ference equality.
Assuming:
<div id="a" class="a"></div>
this:
$('div.a')[0] == $('div#a')[0]
returns true.
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Do NSUserDefaults persist through an Update to an app in the Appstore?
Is this the case? Do NSUserDefaults get reset when you submit an update to an app on the App Store, or are they reset?
6 An...
PHP 5: const vs static
In PHP 5, what is the difference between using const and static ?
7 Answers
7
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Deserialize JSON into C# dynamic object?
Is there a way to deserialize JSON content into a C# 4 dynamic type? It would be nice to skip creating a bunch of classes in order to use the DataContractJsonSerializer .
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How do you make Git ignore files without using .gitignore?
...ernal weird constraints I cannot modify the .gitignore of my repository. Is there a way to ignore files and directories other than modifying a .gitignore ? Even if it is a global solution like a global configuration that will be applied to all my repositories.
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How to force R to use a specified factor level as reference in a regression?
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See the relevel() function. Here is an example:
set.seed(123)
x <- rnorm(100)
DF <- data.frame(x = x,
y = 4 + (1.5*x) + rnorm(100, sd = 2),
b = gl(5, 20))
head(DF)
str(DF)
m1 <- lm(y ~ x + b, data = DF)
summary(m1...
What's the significance of Oct 12 1999? [closed]
...people on the ASP.NET Team. The dev who wrote THAT line of code, we think, is gone. We asked The Gu, and he wasn't sure.
Stefan Schackow, from the team, said, after speaking with Manu Vasandani:
"The ASP.NET developers were being
chased by a pack of feral ninjas on
fire and thus were under...