This is something people trip over all the time, even when they know about it. 🙂 You’re seeing this for the same reason parseInt(“1abc”) returns 1: parseInt stops at the first invalid character and returns whatever it has at that point. If there are no valid characters to parse, it returns NaN. parseInt(8, 3) means … Read more
“Integer” is an arbitrary precision type: it will hold any number no matter how big, up to the limit of your machine’s memory…. This means you never have arithmetic overflows. On the other hand it also means your arithmetic is relatively slow. Lisp users may recognise the “bignum” type here. “Int” is the more common … Read more
You could use e.g. r.nextInt(101) For a more generic “in between two numbers” use: Random r = new Random(); int low = 10; int high = 100; int result = r.nextInt(high-low) + low; This gives you a random number in between 10 (inclusive) and 100 (exclusive)
https://groups.google.com/group/golang-nuts/msg/71c307e4d73024ce?pli=1 The germane part: Since integer types use two’s complement arithmetic, you can infer the min/max constant values for int and uint. For example, const MaxUint = ^uint(0) const MinUint = 0 const MaxInt = int(MaxUint >> 1) const MinInt = -MaxInt – 1 As per @CarelZA’s comment: uint8 : 0 to 255 uint16 : … Read more
More conveniently This can be done more conveniently using Bash’s numeric context: if (( $(echo “$num1 > $num2” |bc -l) )); then … fi Explanation Piping through the basic calculator command bc returns either 1 or 0. The option -l is equivalent to –mathlib; it loads the standard math library. Enclosing the whole expression between … Read more
>>> import re >>> re.sub(“[^0-9]”, “”, “sdkjh987978asd098as0980a98sd”) ‘987978098098098’
Use modulus: function isEven(n) { return n % 2 == 0; } function isOdd(n) { return Math.abs(n % 2) == 1; } You can check that any value in Javascript can be coerced to a number with: Number.isFinite(parseFloat(n)) This check should preferably be done outside the isEven and isOdd functions, so you don’t have to … Read more
You can do <input type=”text” pattern=”\d*”>. This will cause the numeric keyboard to appear. See here for more detail: Text, Web, and Editing Programming Guide for iOS <form> <input type=”text” pattern=”\d*”> <button type=”submit”>Submit</button> </form>
If I’m not mistaken, the question requires “contains number”, not “is number”. So: function hasNumber(myString) { return /\d/.test(myString); }
You may also pass the float value, and use: String.format(“%.2f”, floatValue); Documentation