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How do I check if a string is a number (float)?

...r. I'm not sure that anything much could be faster than the above. It calls the function and returns. Try/Catch doesn't introduce much overhead because the most common exception is caught without an extensive search of stack frames. The issue is that any numeric conversion function has two kin...
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Iterate over the lines of a string

...())' 10000 loops, best of 3: 61.5 usec per loop Note we need the list() call to ensure the iterators are traversed, not just built. IOW, the naive implementation is so much faster it isn't even funny: 6 times faster than my attempt with find calls, which in turn is 4 times faster than a lower-lev...
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When to use symbols instead of strings in Ruby?

...iers. For Ruby < 2.2 only use symbols when they aren't generated dynamically, to avoid memory leaks. Full answer The only reason not to use them for identifiers that are generated dynamically is because of memory concerns. This question is very common because many programming languages don't h...
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Input and output numpy arrays to h5py

I have a Python code whose output is a sized matrix, whose entries are all of the type float . If I save it with the extension .dat the file size is of the order of 500 MB. I read that using h5py reduces the file size considerably. So, let's say I have the 2D numpy array named A . How do I ...
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How to create a density plot in matplotlib?

...with R. This is because gaussian_kde tries to infer the bandwidth automatically. You can play with the bandwidth in a way by changing the function covariance_factor of the gaussian_kde class. First, here is what you get without changing that function: However, if I use the following code: import...
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Parse JSON in C#

...lizeObject(object o); This are already part of Json.NET so you can just call them on the JsonConvert class. Link: Serializing and Deserializing JSON with Json.NET Now, the reason you're getting a StackOverflow is because of your Properties. Take for example this one : [DataMember] public st...
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What is the most robust way to force a UIView to redraw?

...ouble with that, you're likely running into one of these issues: You're calling it before you actually have the data, or your -drawRect: is over-caching something. You're expecting the view to draw at the moment you call this method. There is intentionally no way to demand "draw right now this ver...
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Define make variable at rule execution time

...r are evaluated. In order to create the directory only when out.tar is actually fired, you need to move the directory creation down into the steps: out.tar : $(eval TMP := $(shell mktemp -d)) @echo hi $(TMP)/hi.txt tar -C $(TMP) cf $@ . rm -rf $(TMP) The eval function evaluates a...
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Replace all non-alphanumeric characters in a string

... If you handle unicode a lot, you may also need to keep all non-ASCII unicode symbols: re.sub("[\x00-\x2F\x3A-\x40\x5B-\x60\x7B-\x7F]+", " ", ":%# unicode ΣΘΙП@./\n") – zhazha Jul 13 '16 at 7:43 ...
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TypeScript typed array usage

... You have an error in your syntax here: this._possessions = new Thing[100](); This doesn't create an "array of things". To create an array of things, you can simply use the array literal expression: this._possessions = []; Of the array constructor if you want to se...