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What do 'real', 'user' and 'sys' mean in the output of time(1)?
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Real, User and Sys process time statistics
One of these things is not like the other. Real refers to actual elapsed time; User and Sys refer to CPU time used only by the process.
Real is wall clock time - time from start to finish of the call. This is all elapsed ...
How to convert NSNumber to NSString
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//An example of implementation :
// we set the score of one player to a value
[Game getCurrent].scorePlayer1 = [NSNumber numberWithInteger:1];
// We copy the value in a NSNumber
NSNumber *aNumber = [Game getCurrent].scorePlayer1;
// Conversion of the NSNumber aNumber to a String w...
How exactly does the callstack work?
...ad here on Stack Overflow, and they are all brilliant. But there is still one thing that I didn't fully understand yet.
7 ...
What is a columnar database?
...her a particular architecture/implementation. In other words, there isn't one particular description on how these databases work; indeed, several are build upon traditional, row-oriented, DBMS, simply storing the info in tables with one (or rather often two) columns (and adding the necessary layer ...
Why do python lists have pop() but not push()
Does anyone know why Python's list.append function is not called list.push given that there's already a list.pop that removes and returns the last element (that indexed at -1) and list.append semantic is consistent with that use?
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Difference Between ViewData and TempData?
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In one sentence: TempData are like ViewData with one difference: They only contain data between two successive requests, after that they are destroyed. You can use TempData to pass error messages or something similar.
Although ...
What Does 'Then' Really Mean in CasperJS
...asper.start();
casper.then(function step1() {
this.echo('this is step one');
});
casper.then(function step2() {
this.echo('this is step two');
});
casper.thenOpen('http://google.com/', function step3() {
this.echo('this is step 3 (google.com is loaded)');
});
You can print out all t...
Determine the number of lines within a text file
...ore efficient was regarding memory usage, not necessarily speed. The first one loads the entire contents of the file into an array which means it must allocate at least as much memory as the size of the file. The second merely loops one line at a time so it never has to allocate more than one line's...
How do I have an enum bound combobox with custom string formatting for enum values?
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Nice one. Better overal, but might be overkill for your run-of-the-mill never-will-be-globalized-in-any-way piece of software. (I know, that assumption will turn out to be false later. ;-))
– peSHIr
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Detect and exclude outliers in Pandas data frame
...dataframe and would like to remove all rows that have outliers in at least one column, the following expression would do that in one shot.
df = pd.DataFrame(np.random.randn(100, 3))
from scipy import stats
df[(np.abs(stats.zscore(df)) < 3).all(axis=1)]
description:
For each column, first it...