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What is causing “Unable to allocate memory for pool” in PHP?
...allowing only 32MB is ridiculously low. PHP was designed when servers were 64MB and most scripts were using one php file per page. Nowadays solutions like Magento require more than 10k files (~60Mb in APC). You should allow enough memory so most of php files are always cached. It's not a waste, it's...
Pandas DataFrame Groupby two columns and get counts
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how to access the value of each group which is sum based on the alphabet and word?
– Rahul Goyal
Mar 5 at 2:52
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How to deal with SettingWithCopyWarning in Pandas?
...etitem__ operation may not work.
In general, you should use loc for label-based assignment, and iloc for integer/positional based assignment, as the spec guarantees that they always operate on the original. Additionally, for setting a single cell, you should use at and iat.
More can be found in th...
GLib compile error (ffi.h), but libffi is installed
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If you have a Debian-based Linux OS with apt-get:
sudo apt-get install libffi-dev
With a Redhat-base OS:
yum install libffi-devel
With Alpine Linux:
apk add libffi-dev
...
Why does struct alignment depend on whether a field type is primitive or user-defined?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
.NET data structures: ArrayList, List, HashTable, Dictionary, SortedList, SortedDictionary — Speed,
...d with List<T> for standard collections and Collection<T> as a base class for custom collections. Hashtable has been largely replaced by Dictionary<TKey, TValue>. I would recommend avoiding ArrayList and Hashtable for new code.
– Sam Harwell
M...
How to profile a bash shell script slow startup?
...O question and already posted answers.
There is 4+ answer:
The first is based on @DennisWilliamson's idea but with a lot less of resource consumption
The second was my own (before this;)
The third is based on @fgm answer, but more accurate.
The last use script, scriptreplay and timing file.
Final...
Difference between encoding and encryption
...ters to be transmitted safely, so it may be necessary to encode data using base64 (uses only letters, numbers and two safe characters).
When encoding or decoding, the emphasis is placed on everyone having the same algorithm, and that algorithm is usually well-documented, widely distributed and fair...
How do I use prepared statements in SQlite in Android?
...repared statements in Android all the time, it's quite simple :
SQLiteDatabase db = dbHelper.getWritableDatabase();
SQLiteStatement stmt = db.compileStatement("INSERT INTO Country (code) VALUES (?)");
stmt.bindString(1, "US");
stmt.executeInsert();
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Fast way of counting non-zero bits in positive integer
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I tried adapting Óscar's and Adam's solutions to process the integer in 64-bit and 32-bit chunks, respectively. Both were at least ten times slower than bin(n).count("1") (the 32-bit version took about half again as much time).
On the other hand, gmpy popcount() took about 1/20th of the time of ...