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How do you append to a file in Python?
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You need to open the file in append mode, by setting "a" or "ab" as the mode. See open().
When you open with "a" mode, the write position will always be at the end of the file (an append). You can open with "a+" to allow reading, seek backwards and read (but all writes...
How to remove leading and trailing whitespace in a MySQL field?
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You're looking for TRIM.
UPDATE FOO set FIELD2 = TRIM(FIELD2);
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How can I read command line parameters from an R script?
...roducible example.
I made two files: exmpl.bat and exmpl.R.
exmpl.bat:
set R_Script="C:\Program Files\R-3.0.2\bin\RScript.exe"
%R_Script% exmpl.R 2010-01-28 example 100 > exmpl.batch 2>&1
Alternatively, using Rterm.exe:
set R_TERM="C:\Program Files\R-3.0.2\bin\i386\Rterm.exe"
%R_TER...
How to get line count of a large file cheaply in Python?
I need to get a line count of a large file (hundreds of thousands of lines) in python. What is the most efficient way both memory- and time-wise?
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How can I check if a file exists in Perl?
...racter special file.
-t
Filehandle is opened to a tty.
-u
File has setuid bit set.
-g
File has setgid bit set.
-k
File has sticky bit set.
-T
File is an ASCII or UTF-8 text file (heuristic guess).
-B
File is a “binary” file (opposite of -T).
-M
Script start time minus...
How JavaScript closures are garbage collected
...closure. I tried two ways to make it unreachable and both work. Either you set some=null when you don't need it anymore, or you set window.f_ = null; and it will be gone.
Update
I have tried it in Chrome 30, FF25, Opera 12 and IE10 on Windows.
The standard doesn't say anything about garbage coll...
memory_get_peak_usage() with “real usage”
If the real_usage argument is set to true the PHP DOCS say it will get the real size of memory allocated from system. If it's false it will get the memory reported by emalloc()
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How to read a file line-by-line into a list?
How do I read every line of a file in Python and store each line as an element in a list?
28 Answers
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What are some uses of template template parameters?
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Say you're using CRTP to provide an "interface" for a set of child templates; and both the parent and the child are parametric in other template argument(s):
template <typename DERIVED, typename VALUE> class interface {
void do_something(VALUE v) {
static_cast...
Fast Linux File Count for a large number of files
I'm trying to figure out the best way to find the number of files in a particular directory when there are a very large number of files ( > 100,000).
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