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Reference - What does this error mean in PHP?

...m. (Note: You might have multiple blocks if you had code that was automatically constructed) Also make sure you don't have any Byte Order Marks in your code, for example when the encoding of the script is UTF-8 with BOM. Related Questions: Headers already sent by PHP All PHP "Headers already sen...
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pandas GroupBy columns with NaN (missing) values

...n the Missing Data section of the docs: NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example. One workaround is to use a placeholder before doing the groupby (e.g. -1): In [11]: df.fillna(-1) Out[11]: a b 0 1 4 1 2 -1 2 3 6 In [12]: df.fil...
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When splitting an empty string in Python, why does split() return an empty list while split('\n') re

...ncorporates both splitting algorithms in the same tool. People seem to mentally model field-splitting as a single concept even though more than one algorithm is involved. share | improve this answer...
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What does static_assert do, and what would you use it for?

...fined (as one would expect in a C++ library). Contrast with having to actually compile SomeLibrary and your code, link everything, and run the executable only then to find out that you spent 30 minutes compiling an incompatible version of SomeLibrary. @Arak, in response to your comment: yes, you ...
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How can I change UIButton title color?

... With Swift 5, UIButton has a setTitleColor(_:for:) method. setTitleColor(_:for:) has the following declaration: Sets the color of the title to use for the specified state. func setTitleColor(_ color: UIColor?, for state: UIControlState) The following Playgro...
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max value of integer

...hine to machine, on embedded systems the int can be 16 bit wide, though usually it is 32 bit. The only requirement is that short int <= int <= long int by size. Also, there is a recommendation that int should represent the native capacity of the processor. All types are signed. The unsigned...
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Windows 7, 64 bit, DLL problems

...++ 32-bit executable on my Windows 7 64-bit development box that also has all those Microsoft applications (Visual Studio 2008 + 2010, TFS, SDK, Microsoft Office)... And it's still running just fine. ...
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Python 3.x rounding behavior

... Python 3's way (called "round half to even" or "banker's rounding") is considered the standard rounding method these days, though some language implementations aren't on the bus yet. The simple "always round 0.5 up" technique results in a sli...
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jekyll markdown internal links

...ou can now post internal links by using the following: [Some Link]({% post_url 2010-07-21-name-of-post %}) This is also referenced in the Jekyll Documentation. https://github.com/mojombo/jekyll/pull/369 share | ...
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What does @: (at symbol colon) mean in a Makefile?

...nd nothing gets done. For example (from Linux's scripts/Makefile.clean): __clean: $(subdir-ymn) ifneq ($(strip $(__clean-files)),) +$(call cmd,clean) endif ifneq ($(strip $(__clean-dirs)),) +$(call cmd,cleandir) endif ifneq ($(strip $(clean-rule)),) +$(clean-rule) endif @: ...