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How to drop a list of rows from Pandas dataframe?
... +1, this is the only answer that tells you how to remove a row selecting a column different from the first one.
– Alejo Bernardin
May 3 at 5:31
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Why does C# not provide the C++ style 'friend' keyword? [closed]
...ly.
Typically, a designer desires to expose only a few private methods to selected few other classes. For example, in a class factory pattern it may be desired that class C1 is instantiated only by class factory CF1. Therefore class C1 may have a protected constructor and a friend class factory C...
sed: print only matching group
... -d " " -f 6-7
Will result in output of:
2 3.4
-d sets the delimiter
-f selects the range of 'fields' to output, in this case, it's the 6th through 7th chunks of the original string. You can also specify the range as a list, such as 6,7.
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“’” showing on page instead of “ ' ”
...tion is wrong. You can also force your web browser to twingle the page by selecting windows-1252 encoding for a utf-8 document. Your web browser cannot detwingle the document that Charlie saved.
Note: the same problem can happen with any other single-byte code page (e.g. latin-1) instead of windo...
Get list of passed arguments in Windows batch script (.bat)
...racters such as &? When I try to retrieve several the path of several selected files (using Send To menu and "%*" which pass the args to a .py) it stops the listing at the & caracters. So if for instance the second file contain a & in its name, the the part of the name after the & w...
Best way to show a loading/progress indicator?
...e.
By the way, Spinner has a different meaning in Android. (It's like the select dropdown in HTML)
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For each row return the column name of the largest value
...s.method = "first")) %>% # or 'last'
filter(dept_rank == 1) %>%
select(-dept_rank)
# A tibble: 3 x 3
# Groups: id [3]
id dept cnt
<chr> <chr> <dbl>
1 2 V1 8.
2 3 V2 5.
3 1 V3 9.
# if you wanted to keep the original wide data f...
Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
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select <column> from <table> group by 1 having count(*) > 1; will give a report on duplicated values.
– Jasen
Aug 26 '16 at 22:57
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Visual Studio popup: “the operation could not be completed”
... elements within the following element. You might want to be a little more selective and try to identify the site that is causing the conflict and remove just that.
<configuration><system.applicationHost><sites>
Note that I left the <siteDefaults>, <applicationDefaults&...
How to use a WSDL file to create a WCF service (not make a call)
...for. Try "Contract First" and WCF. or "WSDL First" and WCF.
Here is a selection:
Basic overview of WSDL-First development with WCF and SvcUtil.exe.
WSCF - A free add-in to Visual Studio enabling Contract-First design with WCF
Introduction to WSCF
A walkthrough of using WSCF
The WSCF proje...