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How to install MySQLdb (Python data access library to MySQL) on Mac OS X?
...aged by mysql were faulty (claimed to be universal but weren't). The data base adapter for Python, MySQLdb, has had its own issues. This is one case where you are well advised to just use MacPorts to build everything you need automatically. It's just too easy for something to go wrong.
...
Do try/catch blocks hurt performance when exceptions are not thrown?
...r version), but it was no difference in the Release version.
Conclution:
Based on these test, I think we can say that Try/Catch does have a small impact on performance.
EDIT:
I tried to increase the loop value from 10000000 to 1000000000, and ran again in Release to get some differences in the re...
How to run a program without an operating system?
...n:
an x86 Lenovo Thinkpad T430 laptop with UEFI BIOS 1.16 firmware
an ARM-based Raspberry Pi 3
We will also try them out on the QEMU emulator as much as possible, as that is safer and more convenient for development. The QEMU tests have been on an Ubuntu 18.04 host with the pre-packaged QEMU 2.11....
Hash String via SHA-256 in Java
...
@Sajjad Use your favorite base64 encoding function. I like the one in Apache Commons personally.
– Brendan Long
Oct 22 '13 at 19:34
...
Use Font Awesome icon as CSS content
...to change the font-family to Font Awesome 5 Brands OR Font Awesome 5 Free, based on the type of icon you are trying to render. Also, do not forget to declare font-weight: 900;
a:before {
font-family: "Font Awesome 5 Free";
content: "\f095";
display: inline-block;
padding-right: 3px;
...
How do I analyze a program's core dump file with GDB when it has command-line parameters?
...2'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x0000564583cf2759 in myfunc (i=3) at main.c:7
7 *(int*)(NULL) = i; /* line 7 */
(gdb) bt
#0 0x0000564583cf2759 in myfunc (i=3) at main.c:7
#1 0x0000564583cf2858 in main (argc=3, argv=0x7ffcca4effa8) at main.c:2
So not...
Best practices for circular shift (rotate) operations in C++
...motion rules mean that rotl_template(u16 & 0x11UL, 7) would do a 32 or 64-bit rotate, not 16 (depending on the width of unsigned long). Even uint16_t & uint16_t is promoted to signed int by C++'s integer-promotion rules, except on platforms where int is no wider than uint16_t.
On x86, th...
Python dictionary: Get list of values for list of keys
...
A little speed comparison:
Python 2.7.11 |Anaconda 2.4.1 (64-bit)| (default, Dec 7 2015, 14:10:42) [MSC v.1500 64 bit (AMD64)] on win32
In[1]: l = [0,1,2,3,2,3,1,2,0]
In[2]: m = {0:10, 1:11, 2:12, 3:13}
In[3]: %timeit [m[_] for _ in l] # list comprehension
1000000 loops, best of 3...
Will the base class constructor be automatically called?
Would the age of customer be 2? It seems like the base class's constructor will be called no matter what. If so, why do we need to call base at the end sometimes?
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eclipse升级后启动失败：Heap堆内存不足 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...or
!STACK 1
java.lang.OutOfMemoryError: Java heap space
at java.base/java.util.concurrent.locks.AbstractQueuedSynchronizer.addWaiter(AbstractQueuedSynchronizer.java:651)
at java.base/java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedNanos(AbstractQueuedSynchron...