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Refresh a page using PHP
How can I refresh a page using PHP periodically? If I can not do it by PHP, what is the best recommended scenario?
13 Answe...
Comparing two dataframes and getting the differences
...rames axes are compared with _indexed_same method, and exception is raised if differences found, even in columns/indices order.
If I got you right, you want not to find changes, but symmetric difference. For that, one approach might be concatenate dataframes:
>>> df = pd.concat([df1, df2]...
In a javascript array, how do I get the last 5 elements, excluding the first element?
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You can call:
arr.slice(Math.max(arr.length - 5, 1))
If you don't want to exclude the first element, use
arr.slice(Math.max(arr.length - 5, 0))
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Can HTML checkboxes be set to readonly?
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PS...if you want the checkbox to be in the checked state you need to add checked="checked", not mess with the javascript. The javascript is just there to force mouse clicks to be ignored on the input object, not to set state of th...
Why should I use Deque over Stack?
...ecause it's a subclass of Vector.
Oh, and also Stack has no interface, so if you know you need Stack operations you end up committing to a specific concrete class, which isn't usually a good idea.
Also as pointed out in the comments, Stack and Deque have reverse iteration orders:
Stack<Integer...
Changing column names of a data frame
... Thank you. I think this is somehow annoying with R: Why is it so difficult to change the column name if you do not want to use the index number but the old name :(
– Arne
Mar 18 '14 at 14:41
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CSS: how to add white space before element's content?
...the text-indent property.
p { text-indent: 1em; }
JSFiddle demo
Edit:
If you want the space to be colored, you might consider adding a thick left border to the first letter. (I'd almost-but-not-quite say "instead", because the indent can be an issue if you use both. But it feels dirty to me t...
How to list all the files in a commit?
...d Way (because it's a plumbing command; meant to be programmatic):
$ git diff-tree --no-commit-id --name-only -r bd61ad98
index.html
javascript/application.js
javascript/ie6.js
Another Way (less preferred for scripts, because it's a porcelain command; meant to be user-facing)
$ git show --pretty...
Why do loggers recommend using a logger per class?
...capture the source of the log message (ie. the class writing to the log). If you don't have one logger per class, but instead have one logger for the entire app, you need to resort to more reflection tricks to know where the log messages are coming from.
Compare the following:
Log per class
usi...
How to succinctly write a formula with many variables from a data frame?
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There is a special identifier that one can use in a formula to mean all the variables, it is the . identifier.
y <- c(1,4,6)
d <- data.frame(y = y, x1 = c(4,-1,3), x2 = c(3,9,8), x3 = c(4,-4,-2))
mod <- lm(y ~ ., data = d)
You can also d...