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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 do I pass command-line arguments to a WinForms application?
... two different WinForms applications, AppA & AppB. Both are running .NET 2.0.
6 Answers
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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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Can't connect to local MySQL server through socket '/tmp/mysql.sock
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PratyayPratyay
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Set cURL to use local virtual hosts
...icitly for this: --resolve
Instead of curl -H 'Host: yada.com' http://127.0.0.1/something
use curl --resolve 'yada.com:80:127.0.0.1' http://yada.com/something
What's the difference, you ask?
Among others, this works with HTTPS. Assuming your local server has a certificate for yada.com, the firs...
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) ...
float64 with pandas to_csv
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df.to_csv('pandasfile.csv', float_format='%.3f')
or, if you don't want 0.0001 to be rounded to zero:
df.to_csv('pandasfile.csv', float_format='%g')
will give you:
Bob,0.085
Alice,0.005
in your output file.
For an explanation of %g, see Format Specification Mini-Language.
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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 ...