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Array include any value from another array?
....include?(food) }
=> true
Benchmark script:
require "benchmark"
N = 1_000_000
puts "ruby version: #{RUBY_VERSION}"
CHEESES = %w(chedder stilton brie mozzarella feta haloumi).freeze
FOODS = %w(pizza feta foods bread biscuits yoghurt bacon).freeze
Benchmark.bm(15) do |b|
b.report("&, emp...
Setting environment variables for accessing in PHP when using Apache
I have a Linux environment and I have a PHP Web Application that conditionally runs based on environment variables using getenv in PHP. I need to know how these environment variables need to be set for the application to work correctly. I am not sure how to set this up on Apache.
...
Using multiple delimiters in awk
...n the input field separator.
See another example:
$ cat file
hello#how_are_you
i#am_very#well_thank#you
This file has two fields separators, # and _. If we want to print the second field regardless of the separator being one or the other, let's make both be separators!
$ awk -F"#|_" '{print ...
Equation (expression) parser with precedence?
...ursively, for example, using your sample string,
1+11*5
to do this manually, you would have to read the 1, then see the plus and start a whole new recursive parse "session" starting with 11... and make sure to parse the 11 * 5 into its own factor, yielding a parse tree with 1 + (11 * 5).
This a...
Nullable Foreign Key bad practice?
... read.
Only if you know better than Chris Date "what first normal form really means". If x and y are both nullable, and indeed in some row x and y are both null, then WHERE x=y does not yield true. This proves beyond reasonable doubt that null is not a value (because any real value is always equ...
In CMake, how can I test if the compiler is Clang?
...
A reliable check is to use the CMAKE_<LANG>_COMPILER_ID variables. E.g., to check the C++ compiler:
if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
# using Clang
elseif (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
# using GCC
elseif (CMAKE_CXX_COMPILER_ID STREQ...
bool to int conversion
... 1, 4>5 would evaluate to 0.
EDIT: Jens in the comment said, C99 has _Bool type. bool is a macro defined in stdbool.h header file. true and false are also macro defined in stdbool.h.
§7.16 from C99 says,
The macro bool expands to _Bool.
[..] true which expands to the integer constan...
Integrating the ZXing library directly into my Android application
...de so it hopefully can help others with the same problem as I had ;)
Install Apache Ant - (See this YouTube video for config help)
Download the ZXing source from ZXing homepage and extract it
With the use of Windows Commandline (Run->CMD) navigate to the root directory of the downloaded zxing s...
Apache Spark: map vs mapPartitions?
...
I'm seeing the opposite -- even with very small operations, its faster to call mapPartitions and iterate than call map. I am assuming that this is just the overhead of starting the language engine that will process the map task. (I'm in R, which may have more startup...
List all tables in postgresql information_schema
What is the best way to list all of the tables within PostgreSQL's information_schema?
8 Answers
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