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How to determine if a record is just created or updated in after_save
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It's best to differentiate with an after_update and an after_create. The callbacks can share a common method that takes an argument to indicate if it's a create or update.
– matthuhiggins
Oct 9 '13 at 23:44
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Iterating over every two elements in a list
...+ y)
In Python 3, you can replace izip with the built-in zip() function, and drop the import.
All credit to martineau for his answer to my question, I have found this to be very efficient as it only iterates once over the list and does not create any unnecessary lists in the process.
N.B: This ...
How to check BLAS/LAPACK linkage in NumPy and SciPy?
I am builing my numpy/scipy environment based on blas and lapack more or less based on this walk through.
5 Answers
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Python assigning multiple variables to same value? list behavior
...he behavior, I expect to reassign the values list separately, I mean b[0] and c[0] equal 0 as before.
9 Answers
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static function in C
...ogy to use here? Wouldn't object file be more accurate? From what I understand, a static function is hidden from the linker and the linker does not operate on translation units.
– Steven Eckhoff
Feb 13 '14 at 18:32
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Duplicate and rename Xcode project & associated folders [closed]
...d like to be able to duplicate an entire Xcode project, rename the project and the associated files without Xcode going mental, and without having to manually re-import all files to the project.
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How can I round a number in JavaScript? .toFixed() returns a string?
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It returns a string because 0.1, and powers thereof (which are used to display decimal fractions), are not representable (at least not with full accuracy) in binary floating-point systems.
For example, 0.1 is really 0.100000000000000005551115123125782702118...
Why does C++ need a separate header file?
...ile with the same functions as in the .cpp file. It makes creating classes and refactoring them very difficult, and it adds unnecessary files to the project. And then there is the problem with having to include header files, but having to explicitly check if it has already been included.
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Calling clojure from java
Most of the top google hits for "calling clojure from java" are outdated and recommend using clojure.lang.RT to compile the source code. Could you help with a clear explanation of how to call Clojure from Java assuming you have already built a jar from the Clojure project and included it in the cl...
How do I check if a number is positive or negative in C#?
...f mathematics, computer science, also regular science which use a negative and positive zero. Chemists and physicists for example will sometimes use -0 for a number which was negative and rounded to zero. Definitions only have meaning within a context. When you treat the mathematical definitions you...