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Check if file exists but prevent 404 error in console from showing up [duplicate]
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1 Answer
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Error in if/while (condition) {: missing Value where TRUE/FALSE needed
...pen accidentally as the results of calculations:
if(TRUE && sqrt(-1)) {}
## Error in if (TRUE && sqrt(-1)) { : missing value where TRUE/FALSE needed
To test whether an object is missing use is.na(x) rather than x == NA.
See also the related errors:
Error in if/while (conditi...
Why don't :before and :after pseudo elements work with `img` elements? [duplicate]
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128
The spec says...
Note. This specification does not fully define the interaction of :before...
Where can I download Jai and Jai-imageio? [closed]
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F12 Jump to method -> go back to previous method after making the jump?
I can jump to code if I click in a method name and hit F12. But, is there a keyboard short cut to jump back to the previous code editor location?
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Format number as fixed width, with leading zeros [duplicate]
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Rails - link_to helper with data-* attribute [duplicate]
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219
Just pass them in... Rails has a default :data hash
= link_to body, url, :data => { :foo =&...
How do I fetch a branch on someone else's fork on GitHub? [duplicate]
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$ git remote add theirusername git@github.com:theirusername/reponame.git
$ git fetch theiruserna...
How to change a string into uppercase
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>>> s = 'sdsd'
>>> s.upper()
'SDSD'
See String Methods.
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