大约有 48,000 项符合查询结果（耗时：0.0411秒） [XML]
Benchmarking (python vs. c++ using BLAS) and (numpy)
....1
Dot product benchmark
Code:
import numpy as np
a = np.random.random_sample((size,size))
b = np.random.random_sample((size,size))
%timeit np.dot(a,b)
Results:
System | size = 1000 | size = 2000 | size = 3000 |
netlib BLAS | 1350 ms | 10900 ms | 39200 ms | ...
Best way to use PHP to encrypt and decrypt passwords? [duplicate]
... ' string to be encrypted '; // note the spaces
To Encrypt:
$iv = mcrypt_create_iv(
mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC),
MCRYPT_DEV_URANDOM
);
$encrypted = base64_encode(
$iv .
mcrypt_encrypt(
MCRYPT_RIJNDAEL_128,
hash('sha256', $key, true),
...
Migration: Cannot add foreign key constraint
... $table->increments('id', true);
$table->integer('user_id')->unsigned();
$table->string('priority_name');
$table->smallInteger('rank');
$table->text('class');
$table->timestamps('timecreated');
});
Schema::table('priorities'...
Send file using POST from a Python script
...ding, but you should be able to read through it and see how it works:
user_agent = "image uploader"
default_message = "Image $current of $total"
import logging
import os
from os.path import abspath, isabs, isdir, isfile, join
import random
import string
import sys
import mimetypes
import urllib2
i...
mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to
...
A query may fail for various reasons in which case both the mysql_* and the mysqli extension will return false from their respective query functions/methods. You need to test for that error condition and handle it accordingly.
mysql_* extension:
NOTE The mysql_ functions are deprecate...
How to drop column with constraint?
...'alter table tbloffers drop constraint ['+dc.NAME+N']'
from sys.default_constraints dc
JOIN sys.columns c
ON c.default_object_id = dc.object_id
WHERE
dc.parent_object_id = OBJECT_ID('tbloffers')
AND c.name = N'checkin'
IF @@ROWCOUNT = 0 BREAK
EXEC (@sql)
END
...
Why declare unicode by string in python?
...racters in the string (that is, u'\u2665' is now legal). You can use from __future__ import unicode_literals to make it the default.
This only applies to Python 2; in Python 3 the default is Unicode, and you need to specify a b in front (like b'These are bytes', to declare a sequence of bytes).
...
What does -D_XOPEN_SOURCE do/mean?
... the gcc man page, but did not find this specific option. I did find XOPEN_SOURCE , but there was little explanation of what it does.
...
Case insensitive searching in Oracle
... allows to fine-tune the behaviour of string comparisons by setting the NLS_COMP and NLS_SORT session parameters:
SQL> SET HEADING OFF
SQL> SELECT *
2 FROM NLS_SESSION_PARAMETERS
3 WHERE PARAMETER IN ('NLS_COMP', 'NLS_SORT');
NLS_SORT
BINARY
NLS_COMP
BINARY
SQL>
SQL> SELECT CA...
How do I import the Django DoesNotExist exception?
...mentation:
self.assertRaises(Answer.DoesNotExist, Answer.objects.get, body__exact='<p>User can reply to discussion.</p>')
or better:
with self.assertRaises(Answer.DoesNotExist):
Answer.objects.get(body__exact='<p>User can reply to discussion.</p>')
...