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Exit codes in Python
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What you're looking for in the script is calls to sys.exit(). The argument to that method is returned to the environment as the exit code.
It's fairly likely that the script is never calling the exit method, and that 0 is the default exit code.
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Composer: how can I install another dependency without updating old ones?
I have a project with a few dependencies and I'd like to install another one, but I'd like to keep the others the way they are. So I've edited the composer.json , but if I run composer install , I get the following output:
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How to emulate C array initialization “int arr[] = { e1, e2, e3, … }” behaviour with std::array?
...s question is about not having to specify the number of elements and still allow nested types to be directly initialized.)
This question discusses the uses left for a C array like int arr[20]; . On his answer , @James Kanze shows one of the last strongholds of C arrays, it's unique initializat...
How to write to an existing excel file without overwriting data (using pandas)?
...omething like this might work out:
import pandas
from openpyxl import load_workbook
book = load_workbook('Masterfile.xlsx')
writer = pandas.ExcelWriter('Masterfile.xlsx', engine='openpyxl')
writer.book = book
## ExcelWriter for some reason uses writer.sheets to access the sheet.
## If you leave ...
Automatic Retina images for web sites
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There is a new attribute for the img tag that allows you to add a retina src attribute, namely srcset. No javascript or CSS needed, no double loading of images.
<img src="low-res.jpg" srcset="high-res.jpg 2x">
Browser Support: http://caniuse.com/#search=srcset
O...
Understanding NSRunLoop
... run loop directly, though there are some (networking) components that may allow you to specify which run loop they will use for I/O processing.
A run loop for a given thread will wait until one or more of its input sources has some data or event, then fire the appropriate input handler(s) to proce...
adding x and y axis labels in ggplot2
...You can set the labels with xlab() and ylab(), or make it part of the scale_*.* call.
library("Sleuth2")
library("ggplot2")
ggplot(ex1221, aes(Discharge, Area)) +
geom_point(aes(size=NO3)) +
scale_size_area() +
xlab("My x label") +
ylab("My y label") +
ggtitle("Weighted Scatterplot of W...
Reading binary file and looping over each byte
...hile byte != "":
# Do stuff with byte.
byte = f.read(1)
finally:
f.close()
Python 2.5-2.7
with open("myfile", "rb") as f:
byte = f.read(1)
while byte != "":
# Do stuff with byte.
byte = f.read(1)
Note that the with statement is not available in versio...
Vertically align text next to an image?
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Actually, in this case it's quite simple: apply the vertical align to the image. Since it's all in one line, it's really the image you want aligned, not the text.
<!-- moved "vertical-align:middle" style from span to img ...
Set a default parameter value for a JavaScript function
...S2015, default parameters are in the language specification.
function read_file(file, delete_after = false) {
// Code
}
just works.
Reference: Default Parameters - MDN
Default function parameters allow formal parameters to be initialized with default values if no value or undefined is pass...