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Generate random string/characters in JavaScript
I want a 5 character string composed of characters picked randomly from the set [a-zA-Z0-9] .
77 Answers
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Why do most C developers use define instead of const? [duplicate]
... Bart van Ingen SchenauBart van Ingen Schenau
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How to calculate the difference between two dates using PHP?
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Use this for legacy code (PHP < 5.3). For up to date solution see jurka's answer below
You can use strtotime() to convert two dates to unix time and then calculate the number of seconds between them. From this it's rather easy to calculate different time periods.
$date1 = "2007-03-24";
$dat...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
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Where is this year() function from?
You could also use the reshape2 package for this task:
require(reshape2)
df_melt <- melt(df1, id = c("date", "year", "month"))
dcast(df_melt, year + month ~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 2000 ...
How to set a border for an HTML div tag
...licit about all the border properties. For example:
border:1px solid black;
See Border shorthand property. Although the other bits are optional some browsers don't set the width or colour to a default you'd expect. In your case I'd bet that it's the width that's zero unless specified.
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git ignore exception
I have a gitignore file that makes git ignore *.dll files, and that is actually the behavior I want. However, if I want an exception ( i.e. to be able to commit foo.dll ), how can I achieve this?
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Convert hex color value ( #ffffff ) to integer value
... values from a server (in this form, #xxxxxx , example #000000 for black)
9 Answers
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Is it correct to use alt tag for an anchor link?
Is it correct to use alt tag for an anchor link, something like
7 Answers
7
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Angular.js programmatically setting a form field to dirty
...atically updating some of the fields on my form with a value and I would like to set the field state to $dirty . Doing something like:
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LINQ Distinct operator, ignore case?
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Marc Gravell♦Marc Gravell
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