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How do I test if a variable is a number in Bash?
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One approach is to use a regular expression, like so:
re='^[0-9]+$'
if ! [[ $yournumber =~ $re ]] ; then
echo "error: Not a number" >&2; exit 1
fi
If the value is not necessarily an integer, consider amending the regex appropriately; for instance:
^[0-9]+([.][0-9]+)?$
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What is the maximum number of characters that nvarchar(MAX) will hold?
...re detailed numbers, you should be able to store
(2 ^ 31 - 1 - 2) / 2 = 1'073'741'822 double-byte characters
1 billion, 73 million, 741 thousand and 822 characters to be precise
in your NVARCHAR(MAX) column (unfortunately, that last half character is wasted...)
Update: as @MartinMulder pointed ...
Failed to Attach to Process ID Xcode
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answered Oct 10 '12 at 12:49
Robert ZahmRobert Zahm
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R data formats: RData, Rda, Rds etc
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KenMKenM
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add a comment
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What Regex would capture everything from ' mark to the end of a line?
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answered May 6 '09 at 17:59
Joshua BeldenJoshua Belden
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How to tell Maven to disregard SSL errors (and trusting all certs)?
...es.
-Dmaven.wagon.http.ssl.allowall=true - enable match of the server's X.509 certificate with hostname. If disabled, a browser like check will be used.
-Dmaven.wagon.http.ssl.ignore.validity.dates=true - ignore issues with certificate dates.
Official documentation: http://maven.apache.org/wagon/w...
How to indicate param is optional using inline JSDoc?
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answered Apr 4 '15 at 0:39
czernyczerny
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Deny all, allow only one IP through htaccess
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edited Nov 28 '15 at 19:00
Laizer
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answered Dec...
Why does “while(true)” without “Thread.sleep” cause 100% CPU usage on Linux but not on Windows?
...Let's say you have 4 cores:
With IRIX mode on, 1 fully utilized core is 100% and 4 cores are 400%.
With IRIX mode off, 1 fully utilized core is 25% and 4 cores are 100%.
This means that by default, top on Linux will show an infinite loop as ~100% and Windows will show it as ~25%, and it means ...
Ternary Operator Similar To ?:
...Hi".getClass.getSimpleName |> {x => x.endsWith("$") ? x.init | x}
res0: String = String
scala> List.getClass.getSimpleName |> {x => x.endsWith("$") ? x.init | x}
res1: String = List
Is this adequate for your needs?
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