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Try-finally block prevents StackOverflowError
...s O(2^N) where N is the maximum stack depth.
Imagine the maximum depth is 5
foo() calls
foo() calls
foo() calls
foo() calls
foo() which fails to call foo()
finally calls
foo() which fails to call foo()
finally
foo() cal...
Get the cartesian product of a series of lists?
... 2.6.
import itertools
somelists = [
[1, 2, 3],
['a', 'b'],
[4, 5]
]
for element in itertools.product(*somelists):
print(element)
Which is the same as,
for element in itertools.product([1, 2, 3], ['a', 'b'], [4, 5]):
print(element)
...
What are the differences between json and simplejson Python modules?
...
wim
241k7070 gold badges435435 silver badges577577 bronze badges
answered Apr 3 '09 at 6:59
Devin JeanpierreDevin Jeanpierre
...
How to drop columns by name in a data frame
...exing or the subset function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operator in column indexation :
R> df[ , -which(names(df) %in% c("z","u"))]
x ...
Is APC compatible with PHP 5.4 or PHP 5.5?
It doesn't seem like APC has been updated to coincide with the php 5.4 release (I wish they would have included APC in PHP core like originally planned).
...
Safe String to BigDecimal conversion
...
Bax
3,68633 gold badges3030 silver badges5656 bronze badges
answered Sep 20 '10 at 14:54
Jeroen RosenbergJeroen Rosenberg
...
How to define a two-dimensional array?
...tems; Python calls this
"list comprehension".
# Creates a list containing 5 lists, each of 8 items, all set to 0
w, h = 8, 5;
Matrix = [[0 for x in range(w)] for y in range(h)]
You can now add items to the list:
Matrix[0][0] = 1
Matrix[6][0] = 3 # error! range...
Matrix[0][6] = 3 # valid
Not...
LINGO使用指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...题：
在模型窗口中输入如下代码：
min=2*x1+3*x2;
x1+x2>=350;
x1>=100;
2*x1+x2<=600;
然后点击工具条上的按钮 即可。
例1.2 使用LINGO软件计算6个发点8个收点的最小费用运输问题。产销单位运价如下表。
销地
产地
...
How to get Top 5 records in SqLite?
...
586
SELECT * FROM Table_Name LIMIT 5;
...