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Join strings with a delimiter only if strings are not null or empty

...ple: [...].filter(x => typeof x === 'string' && x.length > 0) will only keep non-empty strings in the list. -- (obsolete jquery answer) var address = "foo"; var city; var state = "bar"; var zip; text = $.grep([address, city, state, zip], Boolean).join(", "); // foo, bar ...
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How to center a “position: absolute” element

...may use: position: absolute; margin-left: auto; margin-right: auto; left: 0; right: 0; text-align: center; share | improve this answer | follow | ...
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Flatten nested dictionaries, compressing keys

...t(items) >>> flatten({'a': 1, 'c': {'a': 2, 'b': {'x': 5, 'y' : 10}}, 'd': [1, 2, 3]}) {'a': 1, 'c_a': 2, 'c_b_x': 5, 'd': [1, 2, 3], 'c_b_y': 10} share | improve this answer | ...
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Could not load type 'System.Runtime.CompilerServices.ExtensionAttribute' from assembly 'mscorlib

... 10 Answers 10 Active ...
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cannot find zip-align when publishing app

...f Android SDK Tools (23 which was released today) and SDK Platform-tools (20 which was also released today). I got an APK out of it, but if I tried to upload it to Google Play I got an error complaining that it is not zip aligned. ...
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What does %~d0 mean in a Windows batch file?

... The magic variables %n contains the arguments used to invoke the file: %0 is the path to the bat-file itself, %1 is the first argument after, %2 is the second and so on. Since the arguments are often file paths, there is some additional syntax to extract parts of the path. ~d is drive, ~p is the...
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How to avoid scientific notation for large numbers in JavaScript?

...tific notation if the number is >= 1e21 and has a maximum precision of 20. Other than that, you can roll your own, but it will be messy. function toFixed(x) { if (Math.abs(x) < 1.0) { var e = parseInt(x.toString().split('e-')[1]); if (e) { x *= Math.pow(10,e-1); x = ...
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How to read data when some numbers contain commas as thousand separator?

...", and then convert the string to numeric using as.numeric: y <- c("1,200","20,000","100","12,111") as.numeric(gsub(",", "", y)) # [1] 1200 20000 100 12111 This was also answered previously on R-Help (and in Q2 here). Alternatively, you can pre-process the file, for instance with sed in unix...
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How does collections.defaultdict work?

...efault items are created using int(), which will return the integer object 0. For the second example, default items are created using list(), which returns a new empty list object. share | improve ...
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What is the best way to determine the number of days in a month with JavaScript?

... 201 function daysInMonth (month, year) { // Use 1 for January, 2 for February, etc. return n...