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Remove duplicated rows

... unique(DF) 44708.230 48981.8445 53062.536 51573.276 52844.591 107032.18 100 b # unique(DT) 746.855 776.6145 2201.657 864.932 919.489 55986.88 100 a microbenchmark(duplicated(DF), duplicated(DT)) # Unit: microseconds # expr min lq mean median ...
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mongoDB/mongoose: unique if not null

... As of MongoDB v1.8+ you can get the desired behavior of ensuring unique values but allowing multiple docs without the field by setting the sparse option to true when defining the index. As in: email : {type: String, trim: true, index: tr...
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How would you make two s overlap?

...dth: 300px; height: 200px; z-index: 2; } #content { margin-top: 100px; /* Provide buffer for logo */ } #links { height: 75px; margin-left: 400px; /* Flush links (with a 25px "padding") right of logo */ } <div id="logo"> <img src="https://via.placeholder.com/200x100" ...
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How to call a method after a delay in Android

... Handler(Looper.getMainLooper()).postDelayed({ //Do something after 100ms }, 100) Java final Handler handler = new Handler(Looper.getMainLooper()); handler.postDelayed(new Runnable() { @Override public void run() { //Do something after 100ms } }, 10...
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data.frame rows to a list

...eresting solutions: data("Batting", package = "Lahman") x <- Batting[1:10000, 1:10] library(benchr) library(purrr) benchmark( split = split(x, seq_len(.row_names_info(x, 2L))), mapply = .mapply(function(...) structure(list(...), class = "data.frame", row.names = 1L), x, NULL), purrr ...
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Is it possible to get the iOS 5.1 SDK for Xcode 4.2 on Snow Leopard?

... +100 To get Xcode 4.2 on Snow Leopard to run code on a device running iOS 5.1 you can do this: If you have another Mac running Lion and...
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Specifying and saving a figure with exact size in pixels

...ixels, you could do the following: plt.figure(figsize=(3.841, 7.195), dpi=100) ( your code ...) plt.savefig('myfig.png', dpi=1000) Note that I used the figure dpi of 100 to fit in most screens, but saved with dpi=1000 to achieve the required resolution. In my system this produces a png with 3840x...
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Force R to stop plotting abbreviated axis labels - e.g. 1e+00 in ggplot2

...g for this: require(ggplot2) df <- data.frame(x=seq(1, 1e9, length.out=100), y=sample(100)) # displays x-axis in scientific notation p <- ggplot(data = df, aes(x=x, y=y)) + geom_line() + geom_point() p # displays as you require require(scales) p + scale_x_continuous(labels = comma) ...
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Sanitizing strings to make them URL and filename safe?

... +100 Some observations on your solution: 'u' at the end of your pattern means that the pattern, and not the text it's matching will be ...
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Find integer index of rows with NaN in pandas dataframe

...nding timings: 333 µs ± 9.95 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each) 280 µs ± 220 ns per loop (mean ± std. dev. of 7 runs, 1000 loops each) 313 µs ± 128 ns per loop (mean ± std. dev. of 7 runs, 1000 loops each) 6.84 ms ± 1.59 µs per loop (mean ± std. dev. of 7 runs, 1...