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How to sort a dataframe by multiple column(s)
I want to sort a data.frame by multiple columns. For example, with the data.frame below I would like to sort by column z (descending) then by column b (ascending):
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Looping over a list in Python
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Try this,
x in mylist is better and more readable than x in mylist[:] and your len(x) should be equal to 3.
>>> mylist = [[1,2,3],[4,5,6,7],[8,9,10]]
>>> for x in mylist:
... if len(x)==3:
... print x
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Better way to shuffle two numpy arrays in unison
...use the single array for shuffling and the views for all other purposes.
Example: Let's assume the arrays a and b look like this:
a = numpy.array([[[ 0., 1., 2.],
[ 3., 4., 5.]],
[[ 6., 7., 8.],
[ 9., 10., 11.]],
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Getting the minimum of two values in SQL
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better understandable syntax: return(select minValue = case when @@param1 < @@param2 then @@param1 else @@param2 end). Ok this may not be normalized, i don't know. But it's much more understandable and should be normalized.
– S...
How to simulate a click by using x,y coordinates in JavaScript?
...entFromPoint and HTMLElement.prototype.click(), since at least IE 6, Firefox 5, any version of Chrome and probably any version of Safari you're likely to care about. It will even follow links and submit forms:
document.elementFromPoint(x, y).click();
https://developer.mozilla.org/En/DOM:document...
“No X11 DISPLAY variable” - what does it mean?
I am trying to install a Java application on my Linux machine (Slackware).
10 Answers
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Changing font size and direction of axes text in ggplot2
I am plotting a graph with a categorical variable on the x axis and a numerical variable on the y axis.
7 Answers
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Getting command-line password input in Python
You know how in Linux when you try some Sudo stuff it tells you to enter the password and, as you type, nothing is shown in the terminal window (the password is not shown)?
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Python circular importing?
...em up correctly.
The easiest way to do so is to use import my_module syntax, rather than from my_module import some_object. The former will almost always work, even if my_module included imports us back. The latter only works if my_object is already defined in my_module, which in a circular import ...