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How to convert a string into double and vice versa?
I want to convert a string into a double and after doing some math on it, convert it back to a string.
12 Answers
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MySQL remove all whitespaces from the entire column
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To replace all spaces :
UPDATE `table` SET `col_name` = REPLACE(`col_name`, ' ', '')
To remove all tabs characters :
UPDATE `table` SET `col_name` = REPLACE(`col_name`, '\t', '' )
To remove all new line characters :
UPDATE `table` SET `col_name` = REPLACE(`c...
How to randomize (shuffle) a JavaScript array?
I have an array like this:
58 Answers
58
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How do you check what version of SQL Server for a database using TSQL?
...mentioned in the answer posted by Matt Rogish:
DECLARE @ver nvarchar(128)
SET @ver = CAST(serverproperty('ProductVersion') AS nvarchar)
SET @ver = SUBSTRING(@ver, 1, CHARINDEX('.', @ver) - 1)
IF ( @ver = '7' )
SELECT 'SQL Server 7'
ELSE IF ( @ver = '8' )
SELECT 'SQL Server 2000'
ELSE IF ( @v...
How to determine the current shell I'm working on
...are some environmental variables specific to various shells:
$version is set on tcsh
$BASH is set on bash
$shell (lowercase) is set to actual shell name in csh or tcsh
$ZSH_NAME is set on zsh
ksh has $PS3 and $PS4 set, whereas the normal Bourne shell (sh) only has $PS1 and $PS2 set. This generally...
Efficient string concatenation in C++
I heard a few people expressing worries about "+" operator in std::string and various workarounds to speed up concatenation. Are any of these really necessary? If so, what is the best way to concatenate strings in C++?
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AWK: Access captured group from line pattern
If I have an awk command
6 Answers
6
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Copy to Output Directory copies folder structure but only want to copy files
...ant to copy certain files from a directory into my /bin/ folder. I have set the files (located in /common/browserhawk/ ) to "Copy to Output Directory". However, it copies the folder structure as well: the files are copied to /bin/common/browserhawk/
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Code formatting shortcuts in Android Studio for Operation Systems
...at it doesn't conflict with Ubuntu.
Steps
Go to System Tools → System Settings → Keyboard → Shortcuts tab → System → Lock Screen.
Select the row New Accelerator..., then press any special key with the Alpha key (e.g. Shift + L). You should've successfully changed the keyboard shortcut.
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In the shell, what does “ 2>&1 ” mean?
...about noclobber option and >| syntax###
That's about overwriting:
While set -o noclobber instruct bash to not overwrite any existing file, the >| syntax let you pass through this limitation:
$ testfile=$(mktemp /tmp/testNoClobberDate-XXXXXX)
$ date > $testfile ; cat $testfile
Mon Jan 7 13...