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Swapping column values in MySQL

... 204 I just had to deal with the same and I'll summarize my findings. The UPDATE table SET X=Y, Y=...
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Pandas - How to flatten a hierarchical index in columns

...et the columns to the top level: df.columns = df.columns.get_level_values(0) Note: if the to level has a name you can also access it by this, rather than 0. . If you want to combine/join your MultiIndex into one Index (assuming you have just string entries in your columns) you could: df.column...
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Regular expression to match URLs in Java

... 106 Try the following regex string instead. Your test was probably done in a case-sensitive manner....
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What is Weak Head Normal Form?

... 404 I'll try to give an explanation in simple terms. As others have pointed out, head normal form d...
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Outline effect to text

...stroked text: .strokeme { color: white; text-shadow: -1px -1px 0 #000, 1px -1px 0 #000, -1px 1px 0 #000, 1px 1px 0 #000; } <div class="strokeme"> This text should have a stroke in some browsers </div> I have made a demo for you here And a hovered example is avai...
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What Process is using all of my disk IO

... You're looking for iotop (assuming you've got kernel >2.6.20 and Python 2.5). Failing that, you're looking into hooking into the filesystem. I recommend the former. share | improve...
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Pandas groupby: How to get a union of strings

..._csv(StringIO(data),sep='\s+') In [5]: df Out[5]: A B C 0 1 0.749065 This 1 2 0.301084 is 2 3 0.463468 a 3 4 0.643961 random 4 1 0.866521 string 5 2 0.120737 ! In [6]: df.dtypes Out[6]: A int64 B float64 C object dtype: object When...
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What's the simplest way to test whether a number is a power of 2 in C++?

... 190 (n & (n - 1)) == 0 is best. However, note that it will incorrectly return true for n=0, so i...
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Adding gif image in an ImageView in android

... 80 First, copy your GIF image into Asset Folder of your app create following classes and paste the ...
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How to check if hex color is “too black”?

...Int(c, 16); // convert rrggbb to decimal var r = (rgb >> 16) & 0xff; // extract red var g = (rgb >> 8) & 0xff; // extract green var b = (rgb >> 0) & 0xff; // extract blue var luma = 0.2126 * r + 0.7152 * g + 0.0722 * b; // per ITU-R BT.709 if (luma < 40) { ...