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How to clear variables in ipython?
...nd I get bad surprises when variables haven't been cleared. How do I clear all variables?
And is it possible to force this somehow every time I invoke the magic command %run?
...
using extern template (C++11)
...t file size.
For example:
// header.h
template<typename T>
void ReallyBigFunction()
{
// Body
}
// source1.cpp
#include "header.h"
void something1()
{
ReallyBigFunction<int>();
}
// source2.cpp
#include "header.h"
void something2()
{
ReallyBigFunction<int>();
}
...
Determine the data types of a data frame's columns
...ation as a vector (i.e. you don't need it to do something else programmatically later), just use str(foo).
In both cases foo would be replaced with the name of your data frame.
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Bootstrap 3 - Why is row class is wider than its container?
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In all grid systems, there are gutters between each column. Bootstrap's system sets a 15px padding on both the left and the right of each column to create this gutter.
The issue is that the first column should not have half a g...
Cleaning `Inf` values from an R dataframe
...ption 1
Use the fact that a data.frame is a list of columns, then use do.call to recreate a data.frame.
do.call(data.frame,lapply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal copying.
DT <- data.table(dat)...
ERROR 1044 (42000): Access denied for user ''@'localhost' to database 'db'
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how can I go to bash?I had problem installing mysql see here superuser.com/questions/377679/… I just know abt it in command line
– Nickool
Jan 12 '12 at 17:01
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What's the valid way to include an image with no src?
I have an image that I will dynamically populate with a src later with javascript but for ease I want the image tag to exist at pageload but just not display anything. I know <img src='' /> is invalid so what's the best way to do this?
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Should I use Java's String.format() if performance is important?
We have to build Strings all the time for log output and so on. Over the JDK versions we have learned when to use StringBuffer (many appends, thread safe) and StringBuilder (many appends, non-thread-safe).
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Difference between val() and text()
...ut element -- regardless of type. .text() gets the innerText (not HTML) of all the matched elements:
.text()
The result is a string that contains
the combined text contents of all
matched elements. This method works on
both HTML and XML documents. Cannot be
used on input elements. For i...
CSS3 Spin Animation
... because you explained it best and you are the only answer that included all the prefixed versions.
– iambriansreed
Feb 13 '13 at 18:07
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