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Script parameters in Bash
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125
The arguments that you provide to a bashscript will appear in the variables $1 and $2 and $3 wh...
Splitting a list into N parts of approximately equal length
... equal parts? For example, if the list has 7 elements and is split it into 2 parts, we want to get 3 elements in one part, and the other should have 4 elements.
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LINGO使用指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...求解如下的LP问题：
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。
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pandas GroupBy columns with NaN (missing) values
...e groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fillna(-1).groupby('b').sum()
Out[12]:
a
b
-1 2
4 1
6 3
That said, this feels pretty awful hack... perhaps there should be an option to include NaN in groupby (see this github issue ...
How do I remove leading whitespace in Python?
I have a text string that starts with a number of spaces, varying between 2 & 4.
5 Answers
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How to merge 2 JSON objects from 2 files using jq?
...t will merge them recursively. For example,
jq -s '.[0] * .[1]' file1 file2
Important: Note the -s (--slurp) flag, which puts files in the same array.
Would get you:
{
"value1": 200,
"timestamp": 1382461861,
"value": {
"aaa": {
"value1": "v1",
"value2": "v2",
"value3...
How to swap keys and values in a hash
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286
Ruby has a helper method for Hash that lets you treat a Hash as if it was inverted (in essence...
How to pip install a package with min and max version range?
... install a package with both a minimum version ( pip install package>=0.2 ) and a maximum version which should never be installed (theoretical api: pip install package<0.3 ).
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what is the unsigned datatype?
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answered Jul 23 '09 at 13:46
Martin v. LöwisMartin v. Löwis
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