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Use 'import module' or 'from module import'?
... * can be particularly useful, if using it as: if(windows):\n\t from module_win import * \n else: \n\t from module_lin import *. Then your parent module can potentially contain OS independent function names, if the function names in module_lin & module_win have same names. It's like conditionall...
Applying a function to every row of a table using dplyr?
...f Hadley's examples using pmap:
iris %>%
mutate(Max.Len= purrr::pmap_dbl(list(Sepal.Length, Petal.Length), max))
Using this approach, you can give an arbitrary number of arguments to the function (.f) inside pmap.
pmap is a good conceptual approach because it reflects the fact that when ...
When should I use C++ private inheritance?
...ly, which is not the case with plain inheritance.
– j_random_hacker
Mar 18 '09 at 8:23
5
This can...
How to force use of overflow menu on devices with menu button
...droid.com/apk/res/android" >
<item
android:id="@+id/menu_overflow"
android:icon="@drawable/abs__ic_menu_moreoverflow_normal_holo_light"
android:orderInCategory="11111"
android:showAsAction="always">
<menu>
<item
...
More elegant way of declaring multiple variables at the same time
...ension, but here's a very readable implementation:
>>> def invert_dict(inverted_dict):
... elements = inverted_dict.iteritems()
... for flag_value, flag_names in elements:
... for flag_name in flag_names:
... yield flag_name, flag_value
...
>>> flags =...
Vagrant stuck connection timeout retrying
...anage list runningvms
This will result in something like this:
"projects_1234567890" {5cxxxx-cxxx-4xxx-8xxx-5xxxxxxxxxx}
Quite often, the VM is simply waiting for you to select an option in the bootloader. You can send the appropriate keycode (in the case, Enter) to the vm with controlvm:
vbo...
How do I parse a string to a float or int?
...
Python method to check if a string is a float:
def is_float(value):
try:
float(value)
return True
except:
return False
A longer and more accurate name for this function could be: is_convertible_to_float(value)
What is, and is not a float in Python may surpris...
how to clear the screen in python [duplicate]
... To avoid the 0 (system's return value) being shown, use absolutely_unused_variable = os.system("cls") or absolutely_unused_variable = os.system("clear")
– Shiva
Jul 4 '15 at 8:01
...
error: cannot dynamic_cast ‘b’ (of type ‘class Base*’) to type ‘c...
error: cannot dynamic_cast ‘b’ (of type ‘class Base*’) to type ‘class Derived*’ (source type is not polymorphic)在将父类型转换为子类型时,可以使用static_cast和dynamic_cast.如果使用dynamic_cast,它要求父类必须为多态的,即要求至少有一个虚函数,因此....
MFC的DDX和DDV技巧 - C/C++ - 清泛网 - 专注C/C++及内核技术
...件关系的成员变量的声明，代码：
// Dialog Data
//{{AFX_DATA(CMyDlg)
enum { IDD = IDD_DIALOG5 };
int m_edit;
//}}AFX_DATA
２． 在 .CPP文件中的类构造函数告终代码处，增加数据成员变量的一些初始化代码
CMyDlg::CMyDlg(CWnd* pParent )
...