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How do I check for null values in JavaScript?
... will check for empty strings (""), null, undefined, false and the numbers 0 and NaN
Please note that if you are specifically checking for numbers it is a common mistake to miss 0 with this method, and num !== 0 is preferred (or num !== -1 or ~num (hacky code that also checks against -1)) for funct...
What are best practices for validating email addresses on iOS 2.0
... the cleanest way to validate an email address that a user enters on iOS 2.0?
13 Answers
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Bash command to sum a column of numbers [duplicate]
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10 Answers
10
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How do I update an NPM module that I published?
I created a NPM module and I published it at version 0.0.1
5 Answers
5
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Return positions of a regex match() in Javascript?
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answered Feb 19 '10 at 10:49
GumboGumbo
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How to create json by JavaScript for loop?
...ID"); // this works too
var status = document.getElementsByName("status")[0];
var jsonArr = [];
for (var i = 0; i < status.options.length; i++) {
jsonArr.push({
id: status.options[i].text,
optionValue: status.options[i].value
});
}
</script>
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How to get all subsets of a set? (powerset)
..., you can just change the range statement to range(1, len(s)+1) to avoid a 0-length combination.
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Generate random 5 characters string
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$rand = substr(md5(microtime()),rand(0,26),5);
Would be my best guess--Unless you're looking for special characters, too:
$seed = str_split('abcdefghijklmnopqrstuvwxyz'
.'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
.'0123456789!@#$%^&*()...
How to position a div in the middle of the screen when the page is bigger than the screen
...it at http://jsfiddle.net/XEUbc/1/
#mydiv {
position:fixed;
top: 50%;
left: 50%;
width:30em;
height:18em;
margin-top: -9em; /*set to a negative number 1/2 of your height*/
margin-left: -15em; /*set to a negative number 1/2 of your width*/
border: 1px solid #ccc;
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R programming: How do I get Euler's number?
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150
The R expression
exp(1)
represents e, and
exp(2)
represents e^2.
This works because exp i...