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What is the difference between BIT and TINYINT in MySQL?
...all end up occupying a whole byte, but semantically BIT would be much more appropriate.
– MestreLion
Feb 23 '19 at 3:20
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C++中判断文件、目录是否存在的几种方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
...
if(fh == NULL)
{
printf("%s","can not open the file");
}
三、_access
当然C中还有一种方式是直接调用c的函数库。
就是函数 int _access(const char* path,int mode);
这个函数的功能十分强大。
可以看看msdn的详细介绍
#include <io.h>
#include ...
How do you create nested dict in Python?
...he following:
d = {} # can use defaultdict(dict) instead
for row in file_map:
# derive row key from something
# when using defaultdict, we can skip the next step creating a dictionary on row_key
d[row_key] = {}
for idx, col in enumerate(row):
d[row_key][idx] = col
Ac...
jQuery find events handlers registered with an object
...ta. Read this jQuery blog post. You should now use this instead:
jQuery._data( elem, "events" );
elem should be an HTML Element, not a jQuery object, or selector.
Please note, that this is an internal, 'private' structure, and shouldn't be modified. Use this for debugging purposes only.
In o...
Remove duplicate elements from array in Ruby
...
Just another alternative if anyone cares.
You can also use the to_set method of an array which converts the Array into a Set and by definition, set elements are unique.
[1,2,3,4,5,5,5,6].to_set => [1,2,3,4,5,6]
...
What is the difference between shallow copy, deepcopy and normal assignment operation?
... @grc But I have tried an example(I remove the new line here.) list_=[[1,2],[3,4]] newlist = list_.copy() list_[0]=[7,8] print(list_) print(newlist) The newlist still display [[1, 2], [3, 4]]. But list_[0] is a list which is mutable.
– Alston
Nov 12 '16...
Rails: around_* callbacks
...classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
...
Dynamically updating plot in matplotlib
...t matplotlib.pyplot as plt
import numpy
hl, = plt.plot([], [])
def update_line(hl, new_data):
hl.set_xdata(numpy.append(hl.get_xdata(), new_data))
hl.set_ydata(numpy.append(hl.get_ydata(), new_data))
plt.draw()
Then when you receive data from the serial port just call update_line.
...
Determine if 2 lists have the same elements, regardless of order? [duplicate]
...side of the esoteric case of unhashable and unsortable elements.
def equal_ignore_order(a, b):
""" Use only when elements are neither hashable nor sortable! """
unmatched = list(b)
for element in a:
try:
unmatched.remove(element)
except ValueError:
...
Bamboo Vs. Hudson(a.k.a. Jenkins) vs Any other CI systems [closed]
...is maybe pie in the sky, but is there something that can also build IPhone apps?
Similar to the answer to your first question, most CI servers will be able to build iPhone apps in some ways. It's possible that there is a little more scripting required though.
Price: Bamboo is not free(apart from...