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What is the most elegant way to remove a path from the $PATH variable in Bash?
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Here's the simplest solution i can devise:
#!/bin/bash
IFS=:
# convert it to an array
t=($PATH)
unset IFS
# perform any array operations to remove elements from the array
t=(${t[@]%%*usr*})
IFS=:
# output the new array
echo "${t[*]}"
The above example will remove any element in $PATH t...
How to set auto increment primary key in PostgreSQL?
I have a table in PostgreSQL with 22 columns, and I want to add an auto increment primary key.
7 Answers
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Compare double to zero using epsilon
Today, I was looking through some C++ code (written by somebody else) and found this section:
11 Answers
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How to repeat a string a variable number of times in C++?
... @Brent The OP asked for both - "'n' spaces (or any string)", and then goes on to demonstrate their intent with a single period as the string. English is not many people's first language so you sometimes need to guess their exact requirements and when analysed, the question is really as...
Better techniques for trimming leading zeros in SQL Server?
...both Leading and Trailing zero's.
--Avoid losing those Trailing zero's and converting embedded spaces into more zeros.
--I added a non-whitespace character ("_") to retain trailing zero's after calling Replace().
--Simply remove the RTrim() function call if you want to preserve trailing spaces.
--If...
Understanding FFT output
...tputs because you are using a complex to complex FFT. Remember that you've converted your 32 samples into 64 values (or 32 complex values) by extending it with zero imaginary parts. This results in a symetric FFT output where the frequency result occurs twice. Once ready to use in the outputs 0 to N...
Format floats with standard json module
... it gives "Map object is not JSON serializable" error, but you can resolve converting the map() to a list with list( map(pretty_floats, obj) )
– Guglie
Oct 11 '18 at 23:54
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What does the “__block” keyword mean?
...eated in a special way when it is used inside a block. Normally, variables and their contents that are also used in blocks are copied, thus any modification done to these variables don't show outside the block. When they are marked with __block, the modifications done inside the block are also visib...
SELECT INTO a table variable in T-SQL
...' to go into the UserData 'name' variable but you are selecting 'location' and somehow assigning it to the UserData 'oldlocation' variable. Will SQL just map these automatically or will it throw some kind of exception?
– Aran Mulholland
Nov 17 '15 at 7:23
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Setting default values for columns in JPA
Is it possible to set a default value for columns in JPA, and if, how is it done using annotations?
18 Answers
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