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Length of generator output [duplicate]
...nything similar for lazy iterables represented by generator comprehensions and functions. Of course, it is not hard to write something like:
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How to add column if not exists on PostgreSQL?
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Here's a short-and-sweet version using the "DO" statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THE...
php execute a background process
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Assuming this is running on a Linux machine, I've always handled it like this:
exec(sprintf("%s > %s 2>&1 & echo $! >> %s", $cmd, $outputfile, $pidfile));
This launches the command $cmd, redirects the command output to $outputfile, and writes the process id to...
How to send email attachments?
I am having problems understanding how to email an attachment using Python. I have successfully emailed simple messages with the smtplib . Could someone please explain how to send an attachment in an email. I know there are other posts online but as a Python beginner I find them hard to understand....
Most concise way to convert a Set to a List
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... and thereby radically defying the Java code conventions: oracle.com/technetwork/java/javase/documentation/… ! :) :)
– Håvard Geithus
Feb 1 '14 at 0:49
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Split column at delimiter in data frame [duplicate]
... rename it appropriately (the rename function from the reshape package is handy for doing this on the fly) and then rbind it with the existing data frame -- extra effort to get it inserted in place of the previous single column rather than as the first or last columns ...
– Ben...
What are some uses of template template parameters?
... all specializations of H.
NOTE: I've been programming c++ for many years and have only needed this once. I find that it is a rarely needed feature (of course handy when you need it!).
I've been trying to think of good examples, and to be honest, most of the time this isn't necessary, but let's co...
How to get the Full file path from URI
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Use:
String path = yourAndroidURI.uri.getPath() // "/mnt/sdcard/FileName.mp3"
File file = new File(new URI(path));
or
String path = yourAndroidURI.uri.toString() // "file:///mnt/sdcard/FileName.mp3"
File file = new File(new URI(path));
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What does the Visual Studio “Any CPU” target mean?
... AnyCPU assembly will JIT to 64-bit code when loaded into a 64-bit process and 32 bit when loaded into a 32-bit process.
By limiting the CPU you would be saying: There is something being used by the assembly (something likely
unmanaged) that requires 32 bits or 64 bits.
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What happens when a computer program runs?
...tem, but modern OSes with virtual memory tend to load their process images and allocate memory something like this:
+---------+
| stack | function-local variables, return addresses, return values, etc.
| | often grows downward, commonly accessed via "push" and "pop" (but can be
| ...