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Reference — What does this symbol mean in PHP?
This is a collection of questions that come up every now and then about syntax in PHP. This is also a Community Wiki, so everyone is invited to participate in maintaining this list.
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Difference between break and continue statement
Can anyone tell me the difference between break and continue statements?
21 Answers
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How to randomize (or permute) a dataframe rowwise and columnwise?
I have a dataframe (df1) like this.
8 Answers
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pandas dataframe columns scaling with sklearn
I have a pandas dataframe with mixed type columns, and I'd like to apply sklearn's min_max_scaler to some of the columns. Ideally, I'd like to do these transformations in place, but haven't figured out a way to do that yet. I've written the following code that works:
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Adding a column to a data.frame
I have the data.frame below. I want to add a column that classifies my data according to column 1 ( h_no ) in that way that the first series of h_no 1,2,3,4 is class 1, the second series of h_no (1 to 7) is class 2 etc. such as indicated in the last column.
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Use CSS3 transitions with gradient backgrounds
I'm trying to transition on hover with css over a thumbnail so that on hover, the background gradient fades in. The transition isn't working, but if I simply change it to an rgba() value, it works fine. Are gradients not supported? I tried using an image too, it won't transition the image either.
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How do I measure separate CPU core usage for a process?
Is there any way to measure a specific process CPU usage by cores?
8 Answers
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Are +0 and -0 the same?
Reading through the ECMAScript 5.1 specification , +0 and -0 are distinguished.
9 Answers
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How to profile a bash shell script slow startup?
My bash shell takes up to 3-4 seconds to start up, while if I start it with --norc it runs immediately.
7 Answers
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Swift Beta performance: sorting arrays
I was implementing an algorithm in Swift Beta and noticed that the performance was very poor. After digging deeper I realized that one of the bottlenecks was something as simple as sorting arrays. The relevant part is here:
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