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combinations between two lists?
...e looking for - see the other answers.
Suppose len(list1) >= len(list2). Then what you appear to want is to take all permutations of length len(list2) from list1 and match them with items from list2. In python:
import itertools
list1=['a','b','c']
list2=[1,2]
[list(zip(x,list2)) for x in ite...
Hash Map in Python
...
253
Python dictionary is a built-in type that supports key-value pairs.
streetno = {"1": "Sachin ...
How does the extend() function work in jQuery?
...nd works, so I ran a little test:
var a = {foo: 1, bar: 1};
var b = {foo: 2, baz: 2};
var c = {foo: 3};
var r = jQuery.extend(a,b,c);
console.log("A: Foo=" + a.foo + " Bar=" + a.bar + " Baz=" + a.baz);
console.log("B: Foo=" + b.foo + " Bar=" + b.bar + " Baz=" + b.baz);
console.log("C: Foo=" + c.foo...
Why does Math.round(0.49999999999999994) return 1?
....1 This is a specification bug, for precisely this one pathological case.2 Java 7 no longer mandates this broken implementation.3
The problem
0.5+0.49999999999999994 is exactly 1 in double precision:
static void print(double d) {
System.out.printf("%016x\n", Double.doubleToLongBits(d));
}
...
Why does ~True result in -2?
...
240
int(True) is 1.
1 is:
00000001
and ~1 is:
11111110
Which is -2 in Two's complement1
1 ...
搭建高可用mongodb集群（一）——配置mongodb - 大数据 & AI - 清泛网 - 专...
...test/single/data
#进入mongodb文件夹
cd /data/mongodbtest/single
2、下载mongodb的安装程序包
wget http://fastdl.mongodb.org/linux/mongodb-linux-x86_64-2.4.6.tgz
#解压下载的压缩包
tar xvzf mongodb-linux-x86_64-2.4.6.tgz
#进入mongodb程序执行文件夹
cd mon...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...
Where is this year() function from?
You could also use the reshape2 package for this task:
require(reshape2)
df_melt <- melt(df1, id = c("date", "year", "month"))
dcast(df_melt, year + month ~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 ...
How to extract the n-th elements from a list of tuples?
... |
edited Mar 6 '19 at 20:33
cs95
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answer...
How do you test that a Python function throws an exception?
...
724
Use TestCase.assertRaises (or TestCase.failUnlessRaises) from the unittest module, for example:...
Centering controls within a form in .NET (Winforms)? [duplicate]
...
254
You could achieve this with the use of anchors. Or more precisely the non use of them.
Contr...