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Frequency table for a single variable

...es = pandas.Series([1,2,2,3,3,3, "fred", 1.8, 1.8]) >>> my_series 0 1 1 2 2 2 3 3 4 3 5 3 6 fred 7 1.8 8 1.8 >>> counts = my_series.value_counts() >>> counts 3 3 2 2 1.8 2 fred 1 1 1 >>> len(c...
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How can I find the number of days between two Date objects in Ruby?

... 10 Answers 10 Active ...
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How to round to 2 decimals with Python?

... edited Nov 26 '19 at 18:40 Boris 4,69255 gold badges4242 silver badges5252 bronze badges answered Dec 8...
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How to find all serial devices (ttyS, ttyUSB, ..) on Linux without opening them?

...ystem should contain plenty information for your quest. My system (2.6.32-40-generic #87-Ubuntu) suggests: /sys/class/tty Which gives you descriptions of all TTY devices known to the system. A trimmed down example: # ll /sys/class/tty/ttyUSB* lrwxrwxrwx 1 root root 0 2012-03-28 20:43 /sys/class/...
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how do I work around log4net keeping changing publickeytoken

We have an asp.net 4.0 project which uses a couple of frameworks which is dependent on log4net version 1.2.10.0. Today I tried to include a new framework which is dependent on log4net version 1.2.11.0, I've been stuck ever since: ...
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Can I automatically increment the file build version when using Visual Studio?

...ally increment the build (and version?) of my files using Visual Studio (2005). 25 Answers ...
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How to decide font color in white or black depending on background color?

...overall intensity of the color and choose the corresponding text. if (red*0.299 + green*0.587 + blue*0.114) > 186 use #000000 else use #ffffff The threshold of 186 is based on theory, but can be adjusted to taste. Based on the comments below a threshold of 150 may work better for you. Edit: T...
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What's the fastest way to loop through an array in JavaScript?

...yntactically obvious). A standard for-loop with length caching var i = 0, len = myArray.length; while (i < len) { // your code i++ } I would say, this is definitely a case where I applaud JavaScript engine developers. A runtime should be optimized for clarity, not cle...
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Pandas: drop a level from a multi-level column index?

...pd.DataFrame([[1,2], [3,4]], columns=cols) >>> df a b c 0 1 2 1 3 4 [2 rows x 2 columns] >>> df.columns = df.columns.droplevel() >>> df b c 0 1 2 1 3 4 [2 rows x 2 columns] ...
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Formatting a number with exactly two decimals in JavaScript

...ich rounds my numbers to two decimal places. But I get numbers like this: 10.8, 2.4, etc. These are not my idea of two decimal places so how I can improve the following? ...