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RGB to hex and hex to RGB
How to convert colors in RGB format to hex format and vice versa?
50 Answers
50
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Java regex capturing groups indexes
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Capturing and grouping
Capturing group (pattern) creates a group that has capturing property.
A related one that you might often see (and use) is (?:pattern), which creates a group without capturing property, hence named non-capturi...
How to find the largest file in a directory and its subdirectories?
We're just starting a UNIX class and are learning a variety of Bash commands. Our assignment involves performing various commands on a directory that has a number of folders under it as well.
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Should you always favor xrange() over range()?
...might prefer range():
In python 3, range() does what xrange() used to do and xrange() does not exist. If you want to write code that will run on both Python 2 and Python 3, you can't use xrange().
range() can actually be faster in some cases - eg. if iterating over the same sequence multiple time...
Abort makefile if variable not set
...ning an auxiliary function for that:
# Check that given variables are set and all have non-empty values,
# die with an error otherwise.
#
# Params:
# 1. Variable name(s) to test.
# 2. (optional) Error message to print.
check_defined = \
$(strip $(foreach 1,$1, \
$(call __check_defin...
How do I check if a number evaluates to infinity?
...lert(x === Infinity); displays "true". (Admittedly that's an obscure case, and anyone who decides to redefine Infinity, NaN etc should expect odd things to happen.)
– LukeH
Jan 18 '11 at 13:49
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iReport not starting using JRE 8
I have downloaded and installed the iReport 4.5 using te Windows installer. But when I try to start the iReport it shows the splash screen but does not start.
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Cocoa Touch: How To Change UIView's Border Color And Thickness?
... change the background color, but I'd like to also change the border color and thickness, is this possible?
14 Answers
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Why can't decimal numbers be represented exactly in binary?
...e the == operator to compare it to another floating-point number. I understand the principles behind floating-point representation.
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Which cryptographic hash function should I choose?
...Indeed, MD5 is often still used in applications where the smaller key size and speed are beneficial. That said, due to its flaws, researchers recommend the use of other hash functions in new scenarios.
SHA1 has a flaw that allows collisions to be found in theoretically far less than the 2^80 steps ...