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Convert a row of a data frame to vector
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Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
Installing Python 3 on RHEL
I'm trying to install python3 on RHEL using the following steps:
19 Answers
19
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How to check iOS version?
...system version as an indication of device or OS capabilities. There is usually a more reliable method of checking whether a particular feature or class is available.
Checking for the presence of APIs:
For example, you can check if UIPopoverController is available on the current device using NSCla...
How to make a variadic macro (variable number of arguments)
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The reason for ## before VA_ARGS is that it swallows the preceding comma in case the variable-argument list is empty, eg. FOO("a") expands to printf("a"). This is an extension of gcc (and vc++, maybe), C99 requires at least one argument to be present in place of the elli...
Python: avoid new line with print command [duplicate]
...ork on 3.x, you suppress using print('whateverhere', end='') where end normally defaults to '\n'
– Jon Clements♦
Jun 29 '12 at 17:19
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“CAUTION: provisional headers are shown” in Chrome debugger
...ield to find the event related to your resource (use parts of the URL).
Finally, click on the event and see if the info shown tells you something.
For Older Versions of chrome
Type chrome://net-internals in the address bar and hit enter.
Open the page that is showing problems.
Go back to net-int...
Thou shalt not inherit from std::vector
Ok, this is really difficult to confess, but I do have a strong temptation at the moment to inherit from std::vector .
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What is Lazy Loading?
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It's called lazy loading because, like a lazy person, you are putting off doing something you don't want to. The opposite is Eager Loading, where you load something right away, long before you need it.
If you are curious why peop...
Query to list all stored procedures
What query can return the names of all the stored procedures in a SQL Server database
23 Answers
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Database Design for Revisions?
We have a requirement in project to store all the revisions(Change History) for the entities in the database. Currently we have 2 designed proposals for this:
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