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How to select the row with the maximum value in each group
...iple observations for each subject I want to take a subset with only the maximum data value for each record. For example, with a following dataset:
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How do I run msbuild from the command line using Windows SDK 7.1?
...ld in Command Prompt, you simply have to add the directory of the msbuild.exe install on your machine to the PATH environment variable.
You can access the environment variables by:
Right clicking on Computer
Click Properties
Then click Advanced system settings on the left navigation bar
On the next...
python numpy ValueError: operands could not be broadcast together with shapes
In numpy, I have two "arrays", X is (m,n) and y is a vector (n,1)
6 Answers
6
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How to determine whether a given Linux is 32 bit or 64 bit?
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Try uname -m. Which is short of uname --machine and it outputs:
x86_64 ==> 64-bit kernel
i686 ==> 32-bit kernel
Otherwise, not for the Linux kernel, but for the CPU, you type:
cat /proc/cpuinfo
or:
grep flags /proc/cpuinfo
Under "flags" parameter, you will see various va...
Is it possible to override JavaScript's toString() function to provide meaningful output for debuggi
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You can override toString in Javascript as well. See example:
function Foo() {}
// toString override added to prototype of Foo class
Foo.prototype.toString = function() {
return "[object Foo]";
}
var f = new Foo();
console.log("" + f); // console displays [object Foo]
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How do I get a substring of a string in Python?
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>>> x = "Hello World!"
>>> x[2:]
'llo World!'
>>> x[:2]
'He'
>>> x[:-2]
'Hello Worl'
>>> x[-2:]
'd!'
>>> x[2:-2]
'llo Worl'
Python calls this concept "slicing" and it works on more t...
Do on-demand Mac OS X cloud services exist, comparable to Amazon's EC2 on-demand instances? [closed]
Amazon's EC2 service offers a variety of Linux and Windows OS choices, but I haven't found a service offering a similar "rent by the hour" service for a remote Mac OS X virtual machine. Does such a service exist? (iCloud looks to be just a data storage service, rather than a service allowing remot...
How to get values from IGrouping
...gt;();
IEnumerable<IGrouping<int, smth>> groups = list.GroupBy(x => x.id);
IEnumerable<smth> smths = groups.SelectMany(group => group);
List<smth> newList = smths.ToList();
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How to remove local (untracked) files from the current Git working tree
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Random Gaussian Variables
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Jarrett's suggestion of using a Box-Muller transform is good for a quick-and-dirty solution. A simple implementation:
Random rand = new Random(); //reuse this if you are generating many
double u1 = 1.0-rand.NextDouble(); //uniform(0,1] random doubles
double...