You were right in thinking mod was a good place to start. Here is an expression which will return true if $number is even, false if odd: $number % 2 == 0 Works for every integerPHP value, see as well Arithmetic OperatorsPHP. Example: $number = 20; if ($number % 2 == 0) { print “It’s … Read more
Use 1, not 2. js> 2.3 % 1 0.2999999999999998
Use the unary + operator, which converts its operand into a number. + true; // 1 + false; // 0 Note, of course, that you should still sanitise the data on the server side, because a user can send any data to your sever, no matter what the client-side code says.
Instead of step=”any”, which allows for any number of decimal places, use step=”.01″, which allows up to two decimal places. More details in the spec: https://www.w3.org/TR/html/sec-forms.html#the-step-attribute
Use the min attribute like this: <input type=”number” min=”0″>
And you can add a max attribute that will specify the highest possible number that you may insert <input type=”number” max=”999″ /> if you add both a max and a min value you can specify the range of allowed values: <input type=”number” min=”1″ max=”999″ /> The above will still not stop a user from manually … Read more
Using modulus will work: num % 1 != 0 // 23 % 1 = 0 // 23.5 % 1 = 0.5 Note that this is based on the numerical value of the number, regardless of format. It treats numerical strings containing whole numbers with a fixed decimal point the same as integers: ‘10.0’ % 1; … Read more
numbers = [23.23, 0.1233, 1.0, 4.223, 9887.2] for x in numbers: print(“{:10.4f}”.format(x)) prints 23.2300 0.1233 1.0000 4.2230 9887.2000 The format specifier inside the curly braces follows the Python format string syntax. Specifically, in this case, it consists of the following parts: The empty string before the colon means “take the next provided argument to format()” … Read more
function dec2bin(dec) { return (dec >>> 0).toString(2); } console.log(dec2bin(1)); // 1 console.log(dec2bin(-1)); // 11111111111111111111111111111111 console.log(dec2bin(256)); // 100000000 console.log(dec2bin(-256)); // 11111111111111111111111100000000 You can use Number.toString(2) function, but it has some problems when representing negative numbers. For example, (-1).toString(2) output is “-1”. To fix this issue, you can use the unsigned right shift bitwise operator (>>>) to … Read more
how about let isnum = /^\d+$/.test(val);