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isset() and empty() - what to use
...er something is set or not use isset.
Empty checks if the variable is set and if it is it checks it for null, "", 0, etc
Isset just checks if is it set, it could be anything not null
With empty, the following things are considered empty:
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a floa...
Unittest setUp/tearDown for several tests
... is fired at the beginning/end of a scenario of tests? The functions setUp and tearDown are fired before/after every single test.
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Multiple aggregations of the same column using pandas GroupBy.agg()
Is there a pandas built-in way to apply two different aggregating functions f1, f2 to the same column df["returns"] , without having to call agg() multiple times?
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Colspan all columns
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I have IE 7.0, Firefox 3.0 and Chrome 1.0
The colspan="0" attribute in a TD is NOT spanning across all TDs in any of the above browsers.
Maybe not recommended as proper markup practice, but if you give a higher colspan value than the total possible n...
How to read a text file reversely with iterator in C#
I need to process a large file, around 400K lines and 200 M. But sometimes I have to process from bottom up. How can I use iterator (yield return) here? Basically I don't like to load everything in memory. I know it is more efficient to use iterator in .NET.
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WAMP error: Forbidden You don't have permission to access /phpmyadmin/ on this server
I am new to WAMP and I have just installed it today.
33 Answers
33
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Python to print out status bar and percentage
...character (carriage return) resets the cursor to the beginning of the line and allows you to write over what was previously on the line.
from time import sleep
import sys
for i in range(21):
sys.stdout.write('\r')
# the exact output you're looking for:
sys.stdout.write("[%-20s] %d%%" %...
Can I set an opacity only to the background image of a div?
...nnot be done since opacity affects the whole element including its content and there's no way to alter this behavior. You can work around this with the two following methods.
Secondary div
Add another div element to the container to hold the background. This is the most cross-browser friendly meth...
How to use hex color values
I am trying to use hex color values in Swift, instead of the few standard ones that UIColor allows you to use, but I have no idea how to do it.
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Why does Math.round(0.49999999999999994) return 1?
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Summary
In Java 6 (and presumably earlier), round(x) is implemented as floor(x+0.5).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+0.49999999...