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Create directory if it does not exist
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What will -Force actually do? The documentation says "Forces this cmdlet to create an item that writes over an existing read-only item". Will it delete an existing folder? It should be clear in this answer.
– Peter Mortensen...
What is `params.require(:person).permit(:name, :age)` doing in Rails 4?
All the examples of strong parameters in Rails 4 docs use
2 Answers
2
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Split column at delimiter in data frame [duplicate]
...b','b|c','x|y'))
library(splitstackshape)
cSplit(df, "FOO", "|")
# ID FOO_1 FOO_2
# 1 11 a b
# 2 12 b c
# 3 13 x y
This particular function also handles splitting multiple columns, even if each column has a different delimiter:
df <- data.frame(ID=11:13,
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bool to int conversion
... 1, 4>5 would evaluate to 0.
EDIT: Jens in the comment said, C99 has _Bool type. bool is a macro defined in stdbool.h header file. true and false are also macro defined in stdbool.h.
§7.16 from C99 says,
The macro bool expands to _Bool.
[..] true which expands to the integer constan...
Combine --user with --prefix error with setup.py install
...me workaround:
pip install --user --install-option="--prefix=" <package_name>
or
python setup.py install --user --prefix=
Note that there is no text (not even whitespace) after the =.
Do not forget the --user flag.
Installing multiple packages:
Create ~/.pydistutils.cfg (or equivalent...
Is there any sed like utility for cmd.exe? [closed]
...ershell saved me.
For grep there is:
get-content somefile.txt | where { $_ -match "expression"}
or
select-string somefile.txt -pattern "expression"
and for sed there is:
get-content somefile.txt | %{$_ -replace "expression","replace"}
For more detail see Zain Naboulsis blog entry.
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Facebook Graph API, how to get users email?
...ress is to request extended permissions on the email field. The user must allow you to see this and you cannot get the e-mail addresses of the user's friends.
http://developers.facebook.com/docs/authentication/permissions
You can do this if you are using Facebook connect by passing scope=email in...
Catch Ctrl-C in C
...ote this answer seven years ago. Yes, language standards change. If you really must better the world, please add your new answer but leave mine as is. As the answer has my name on it, I'd prefer it to contain my words too. Thank you.
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Should I use the datetime or timestamp data type in MySQL?
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Timestamps in MySQL are generally used to track changes to records, and are often updated every time the record is changed. If you want to store a specific value you should use a datetime field.
If you meant that you want to decide between using a UNIX ...
Why is it important to override GetHashCode when Equals method is overridden?
...ot match, they may never be considered equal (Equals will simply never be called).
The GetHashCode() method should reflect the Equals logic; the rules are:
if two things are equal (Equals(...) == true) then they must return the same value for GetHashCode()
if the GetHashCode() is equal, it is not...