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How to make an element in XML schema optional?
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Try this
<xs:element name="description" type="xs:string" minOccurs="0" maxOccurs="1" />
if you want 0 or 1 "description" elements, Or
<xs:element name="description" type="xs:string" minOccurs="0" maxOccurs="unbounded" />
if you want 0 to infinity number of "description" elements...
How to initialise memory with new operator in C++?
...ay of type int with the new operator, how can I initialise them all to 0 without looping through them all myself? Should I just use memset ? Is there a “C++” way to do it?
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How to append rows to an R data frame
...sive insight than system.time:
library(microbenchmark)
microbenchmark(f1(1000), f3(1000), f4(1000), times = 5)
# Unit: milliseconds
# expr min lq median uq max neval
# f1(1000) 1024.539618 1029.693877 1045.972666 1055.25931 1112.769176 5
# f3(1000) ...
Can't connect to local MySQL server through socket '/tmp/mysql.sock
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PratyayPratyay
1,90611 gold badge1313 silver badges1414 bronze badges
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How to specify Composer install path?
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140
It seems that you can define the vendor dir to be something else (plugins in your case):
{
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How do I get time of a Python program's execution?
...s that your program takes at least a tenth of second to run.
Prints:
--- 0.764891862869 seconds ---
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Add unique constraint to combination of two columns
...g an exception (exceptions are expensive).
http://www.sqlperformance.com/2012/08/t-sql-queries/error-handling
http://www.mssqltips.com/sqlservertip/2632/checking-for-potential-constraint-violations-before-entering-sql-server-try-and-catch-logic/
If you want to prevent exceptions from bubbling up ...
Cluster analysis in R: determine the optimal number of clusters
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1024
If your question is how can I determine how many clusters are appropriate for a kmeans analysi...
Bash Script: count unique lines in file
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306
You can use the uniq command to get counts of sorted repeated lines:
sort ips.txt | uniq -c
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Ruby: Merging variables in to a string
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answered Feb 16 '09 at 21:42
Mike WoodhouseMike Woodhouse
47.6k1212 gold badges8585 silver badges123123 bronze badges
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