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Looking for a clear definition of what a “tokenizer”, “parser” and...
I am looking for a clear definition of what a "tokenizer", "parser" and "lexer" are and how they are related to each other (e.g., does a parser use a tokenizer or vice versa)? I need to create a program will go through c/h source files to extract data declaration and definitions.
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Is there any performance gain in indexing a boolean field?
... think about it like a book. If there were only 3 kinds of words in a book and you index all of them, you would have the same number of index pages as normal pages.
There would be a performance gain if there are relatively few records of one value. For example, if you have 1000 records and 10 of t...
Why is i++ not atomic?
...crement operation atomic; it involves synchronization at both the software and hardware levels that need not be present in an ordinary increment.
You could make the argument that i++ should have been designed and documented as specifically performing an atomic increment, so that a non-atomic increm...
How can I sharpen an image in OpenCV?
... Wikipedia article on unsharp masking:
You use a Gaussian smoothing filter and subtract the smoothed version from the original image (in a weighted way so the values of a constant area remain constant).
To get a sharpened version of frame into image: (both cv::Mat)
cv::GaussianBlur(frame, image, cv:...
javascript: recursive anonymous function?
...ive the function a name, even when you're creating the function as a value and not a "function declaration" statement. In other words:
(function foo() { foo(); })();
is a stack-blowing recursive function. Now, that said, you probably don't may not want to do this in general because there are som...
Why is rbindlist “better” than rbind?
I am going through documentation of data.table and also noticed from some of the conversations over here on SO that rbindlist is supposed to be better than rbind .
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Difference in Months between two dates in JavaScript
..." is subject to a lot of interpretation. :-)
You can get the year, month, and day of month from a JavaScript date object. Depending on what information you're looking for, you can use those to figure out how many months are between two points in time.
For instance, off-the-cuff:
function monthDif...
Can I automatically increment the file build version when using Visual Studio?
I was just wondering how I could automatically increment the build (and version?) of my files using Visual Studio (2005).
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Removing duplicates from a list of lists
...pby(k))
[[1, 2], [3], [4], [5, 6, 2]]
itertools often offers the fastest and most powerful solutions to this kind of problems, and is well worth getting intimately familiar with!-)
Edit: as I mention in a comment, normal optimization efforts are focused on large inputs (the big-O approach) becaus...
What is the difference between “int” and “uint” / “long” and “ulong”?
I know about int and long (32-bit and 64-bit numbers), but what are uint and ulong ?
5 Answers
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