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How to write trycatch in R
...;- tryCatch(
{
# Just to highlight: if you want to use more than one
# R expression in the "try" part then you'll have to
# use curly brackets.
# 'tryCatch()' will return the last evaluated expression
# in case the "try" part was...
How to have the cp command create any necessary folders for copying a file to a destination [duplica
...chy, rsync can do it in one operation. I'm quite a fan of rsync as a much more versatile cp replacement, in fact:
rsync -a myfile /foo/bar/ # works if /foo exists but /foo/bar doesn't. bar is created.
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Why can't I do ?
...ox extensions and IE extensions can access local resources. Chrome is much more restrictive.
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Best way to check for “empty or null value”
...trim() call is (comparatively) expensive - and just not necessary. I added more about char(n) and "empty string".
– Erwin Brandstetter
May 20 '14 at 19:42
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differences in application/json and application/x-www-form-urlencoded
...derstanding is using JSON as contentType helps when the data to be sent is more complex and involves a lot of hierarchy.. whereas form encoded is good to send simple params in url which can be read at the backend without to much code... I guess this answers the why part of it.
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How do you implement a good profanity filter?
...arrays rather than a single long regex, and for long word lists, it may be more manageable. See the preg_replace() for some good examples as to how arrays can be used flexibly.
For additional PHP programming examples, see this page for a somewhat advanced generic class for word filtering that *'s o...
How to write to an existing excel file without overwriting data (using pandas)?
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How to extract a floating number from a string [duplicate]
....findall("\d+\.\d+", "Current Level: 13.4 db.")
['13.4']
may suffice.
A more robust version would be:
>>> re.findall(r"[-+]?\d*\.\d+|\d+", "Current Level: -13.2 db or 14.2 or 3")
['-13.2', '14.2', '3']
If you want to validate user input, you could alternatively also check for a float ...
How to increase the gap between text and underlining in CSS
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PowerShell says “execution of scripts is disabled on this system.”
... this into your PowerShell window:
Set-ExecutionPolicy RemoteSigned
For more information, see Using the Set-ExecutionPolicy Cmdlet.
When you are done, you can set the policy back to its default value with:
Set-ExecutionPolicy Restricted
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