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Numpy how to iterate over columns of array?
...m x n array. I want to pass each column of this array to a function to perform some operation on the entire column. How do I iterate over the columns of the array?
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How do I make a UITableViewCell appear disabled?
I know about UITableview: How to Disable Selection for Some Rows but Not Others and cell.selectionStyle = UITableViewCellSelectionStyleNone , but how do I make a cell (or any UIView for that matter) appear disabled (grayed-out) like below?
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what is faster: in_array or isset? [closed]
This question is merely for me as I always like to write optimized code that can run also on cheap slow servers (or servers with A LOT of traffic)
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Adding a column to a data.frame
...vector
my.dataframe[["new.col"]] <- a.vector
The data.frame method for $, treats x as a list
my.dataframe$new.col <- a.vector
When [ and [[ are used with two indices (x[i, j] and x[[i, j]]) they act like indexing a matrix
my.dataframe[ , "new.col"] <- a.vector
Since the meth...
Best way to represent a fraction in Java?
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It just so happens that I wrote a BigFraction class not too long ago, for Project Euler problems. It keeps a BigInteger numerator and denominator, so it'll never overflow. But it'll be a tad slow for a lot of operations that you know will never overflow.. anyway, use it if you want it. I've ...
How to plot two histograms together in R?
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That image you linked to was for density curves, not histograms.
If you've been reading on ggplot then maybe the only thing you're missing is combining your two data frames into one long one.
So, let's start with something like what you have, two separ...
Accessing localhost:port from Android emulator
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Not working for me right now, but here's the link to the Android docs and it's clear that this is what sould do it (10.0.2.2); developer.android.com/tools/devices/emulator.html
– Stuart Hallows
May ...
What are the minimum margins most printers can handle?
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This is only a safe bet on inkjets made for photo printing. Laser printers usually have a much larger margin. However, the question states that they're producing graphics, so optimizing for inkjets might be OK.
– Kevin Vermeer
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Python: Append item to list N times
This seems like something Python would have a shortcut for. I want to append an item to a list N times, effectively doing this:
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I do not want to inherit the child opacity from the parent in CSS
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This works for background color only, unless text color supports alpha channel? Another similar solution for background is of course the mighty .png :)
– Wesley Murch
Apr 24 '11 at 12:04
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