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pandas three-way joining multiple dataframes on columns
... columns=['name', 'attr31', 'attr32'])
dfs = [df1, df2, df3]
dfs = [df.set_index('name') for df in dfs]
dfs[0].join(dfs[1:])
attr11 attr12 attr21 attr22 attr31 attr32
name
a 5 9 5 19 15 49
b 4 61 14 ...
How to tell if JRE or JDK is installed
...ow you the version of java installed on the system (assuming that you have set the path of the java in system environment).
And if you haven't, add it via
export JAVA_HOME=/path/to/java/jdk1.x
and if you unsure if you have java at all on your system just use find in terminal
i.e. find / -na...
OpenSSL and error in reading openssl.conf file
...
On Windows you can also set the environment property OPENSSL_CONF. For example from the commandline you can type:
set OPENSSL_CONF=c:/libs/openssl-0.9.8k/openssl.cnf
to validate it you can type:
echo %OPENSSL_CONF%
You can also set it as part ...
Git pull without checkout?
...t pull and other commands from within a branch I'm working on. But I have set up a development server that several people work on, so I don't want to have to switch branches when I do it. If I want to update an existing branch on the dev server from the github repository we all use, what would be ...
How do you make Vim unhighlight what you searched for? [duplicate]
...
Just clarifying @steamer25's comment. :set nohlsearch turns off search highlighting completely :nohlsearch or :noh will clear the current highlight, but leave you in hlsearch mode for the next search.
– Hovis Biddle
Mar 25 '1...
Split function equivalent in T-SQL?
...os int
if substring( @sString, 1, 1 ) = @cDelimiter
begin
set @iStart = 2
insert into @tParts
values( null )
end
else
set @iStart = 1
while 1=1
begin
set @iPos = charindex( @cDelimiter, @sString, @iStart )
if @iPos = 0
...
Add unique constraint to combination of two columns
...o.BlockDuplicatesYourTable
ON dbo.YourTable
INSTEAD OF INSERT
AS
BEGIN
SET NOCOUNT ON;
IF NOT EXISTS (SELECT 1 FROM inserted AS i
INNER JOIN dbo.YourTable AS t
ON i.column1 = t.column1
AND i.column2 = t.column2
)
BEGIN
INSERT dbo.YourTable(column1, column2, ...)
SEL...
Removing an activity from the history stack
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You can achieve this by setting the android:noHistory attribute to "true" in the relevant <activity> entries in your AndroidManifest.xml file. For example:
<activity
android:name=".AnyActivity"
android:noHistory="true" />
...
Backbone.View “el” confusion
How should a view's el be handled?
It has to be set, otherwise events don't fire (see here ).
3 Answers
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How do I remove duplicates from a C# array?
...tinct(StringComparer.OrdinalIgnoreCase) to get a case-insensitive distinct set of strings.
– justisb
Oct 13 '15 at 16:26
...