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Reset C int array to zero : the fastest way?

...e is doing something incorrect. #include<immintrin.h> #define intrin_ZERO(a,n){\ size_t x = 0;\ const size_t inc = 32 / sizeof(*(a));/*size of 256 bit register over size of variable*/\ for (;x < n-inc;x+=inc)\ _mm256_storeu_ps((float *)((a)+x),_mm256_setzero_ps());\ if(4 == sizeof(*(a)...
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Minimizing NExpectation for a custom distribution in Mathematica

.... Let's extract it from your definition above into simple functions: pdf[a_, b_, m_, s_, x_] := (1/(2*(a + b)))*a*b* (E^(a*(m + (a*s^2)/2 - x))*Erfc[(m + a*s^2 - x)/(Sqrt[2]*s)] + E^(b*(-m + (b*s^2)/2 + x))*Erfc[(-m + b*s^2 + x)/(Sqrt[2]*s)]) pdf2[a_, b_, m_, s_, x_] := pdf[a, b, m, s, Log...
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Retain cycle on `self` with blocks

...sue is identical to the workaround for the retain issue; namely, using the __block storage class for the variable. In any case, to answer your question, there's no real alternative here. If you're designing your own block-based API, and it makes sense to do so, you could have the block get passed t...
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Undocumented NSURLErrorDomain error codes (-1001, -1003 and -1004) using StoreKit

... -1017, NSURLErrorAppTransportSecurityRequiresSecureConnection NS_ENUM_AVAILABLE(10_11, 9_0) = -1022, NSURLErrorFileDoesNotExist = -1100, NSURLErrorFileIsDirectory = -1101, NSURLErrorNoPermissionsToReadFile = -1102, NSURLErrorDataLengthExceedsMaximum NS_ENUM_AVAILABLE(10...
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What's the difference between using CGFloat and float?

...undation source code, in CoreGraphics' CGBase.h: /* Definition of `CGFLOAT_TYPE', `CGFLOAT_IS_DOUBLE', `CGFLOAT_MIN', and `CGFLOAT_MAX'. */ #if defined(__LP64__) && __LP64__ # define CGFLOAT_TYPE double # define CGFLOAT_IS_DOUBLE 1 # define CGFLOAT_MIN DBL_MIN # define CGFLOAT_MAX DBL_M...
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Python argparse mutual exclusive group

... add_mutually_exclusive_group doesn't make an entire group mutually exclusive. It makes options within the group mutually exclusive. What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd hav...
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How to flush output of print function?

.../python3 to #!/usr/bin/python3 -u - now when you run your script (e.g. ./my_script.py) the -u will always be added for you – James Sep 7 at 17:22 add a comment ...
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Get original URL referer with PHP?

I am using $_SERVER['HTTP_REFERER']; to get the referer Url. It works as expected until the user clicks another page and the referer changes to the last page. ...
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What does enumerate() mean?

What does for row_number, row in enumerate(cursor): do in Python? 5 Answers 5 ...
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Replace multiple characters in one replace call

... Use the OR operator (|): var str = '#this #is__ __#a test###__'; str.replace(/#|_/g,''); // result: "this is a test" You could also use a character class: str.replace(/[#_]/g,''); Fiddle If you want to replace the hash with one thing and the underscore with anothe...