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What is the difference between inversedBy and mappedBy?
...at doctrine can now safely use JOIN SQL statements instead of two separate SELECT statements. Without mappedBy, the doctrine engine would not know from the JOIN statement it will create what variable in the class 'Task' to put the category information.
Hope this explains it a bit better.
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How do I replace NA values with zeros in an R dataframe?
... mutate(myCol1 = if_else(is.na(myCol1), 0, myCol1))
Note: This works per selected column, if we need to do this for all column, see @reidjax's answer using mutate_each.
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What is the smallest possible valid PDF?
... This will not work, you need to define a font resource and select it inside the page content for the text to show up.
– yms
Aug 21 '15 at 20:36
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vs
...out the BOM. A free editor that can is Notepad++. On the program menu bar, select "Encoding > Encode in UTF-8 without BOM". You can also open files and re-save them in UTF-8 using "Encoding > Convert to UTF-8 without BOM".
More on the Byte Order Mark (BOM) at Wikipedia.
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Learning Python from Ruby; Differences and Similarities
...lues greater than 15. In Ruby, you'd have to write the following:
values.select {|v| v > 15}.map {|v| v * v}
The Ruby code doesn't feel as compact. It's also not as efficient since it first converts the values array into a shorter intermediate array containing the values greater than 15. Th...
Why is IoC / DI not common in Python?
...s great use of inversion of control. For instance, the database server is selected by the configuration file, then the framework provides appropriate database wrapper instances to database clients.
The difference is that Python has first-class types. Data types, including classes, are themselves ...
Rails 4 multiple image or file upload using carrierwave
How can I upload multiple images from a file selection window using Rails 4 and CarrierWave? I have a post_controller and post_attachments model. How can I do this?
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The difference between fork(), vfork(), exec() and clone()
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in fork(), either child or parent process will execute based on cpu selection..
But in vfork(), surely child will execute first. after child terminated, parent will execute.
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How can I change my Cygwin home folder after installation?
...nced >> Environment Variables >> User Variables for >> [select variable HOME] >> edit
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Confused about stdin, stdout and stderr?
...se the same library functions and interfaces (printf,
scanf, read, write, select, etc.) without worrying about whether the I/O stream
is connected to a keyboard, a disk file, a socket, a pipe, or some other I/O abstraction.
Most programs need to read input, write output, and log errors, so stdi...