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Tools for analyzing performance of a Haskell program
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how to find out why this solution is so slow. Are there any commands that tell me where most of the computation-time is spend so I know which part of my haskell-program is slow?
Precisely! GHC provides many excellent tools, including:
runtime statistics
time profiling
heap profiling
t...
How to use php serialize() and unserialize()
... means to put the structure into a "lower common denominator" that can be handled by things other than PHP, like databases, text files, sockets. The standard PHP function serialize is just a format to express such a thing, it serializes a data structure into a string representation that's unique to ...
How to validate an email address in JavaScript
... for "RFC822" or "RFC2822" to get a proper regex.
– Randal Schwartz
Sep 8 '10 at 2:34
45
This doe...
Search for string and get count in vi editor
I want to search for a string and find the number of occurrences in a file using the vi editor.
8 Answers
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How do I concatenate multiple C++ strings on one line?
...ilverMöls The OP declares s on a different line in the equivalent C# code and in his non-compiling C++ code. His desired C++ is s += "Hello world, " + "nice to see you, " + "or not."; which can be written s.append("Hello world, ").append("nice to see you, ").append("or not.");
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Concatenating null strings in Java [duplicate]
... s = null;
s = s + "hello";
System.out.println(s); // prints "nullhello"
and compiles it into bytecode as if you had instead written this:
String s = null;
s = new StringBuilder(String.valueOf(s)).append("hello").toString();
System.out.println(s); // prints "nullhello"
(You can do so yourself b...
How to check if running in Cygwin, Mac or Linux?
I have a shell script that is used both on Windows/Cygwin and Mac and Linux. It needs slightly different variables for each versions.
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How to check Oracle database for long running queries
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from v$sqltext_with_newlines t,V$SESSION s
where t.address =s.sql_address
and t.hash_value = s.sql_hash_value
and s.status = 'ACTIVE'
and s.username <> 'SYSTEM'
order by s.sid,t.piece
/
This shows locks. Sometimes things are going slow, but it's because it is blocked waiting for a lock:
s...
How do I get java logging output to appear on a single line?
...ormat from a system property, so adding something like this to the JVM command line will cause it to print on one line:
-Djava.util.logging.SimpleFormatter.format='%1$tY-%1$tm-%1$td %1$tH:%1$tM:%1$tS %4$s %2$s %5$s%6$s%n'
Alternatively, you can also add this to your logger.properties:
java.util....
Cartesian product of x and y array points into single array of 2D points
I have two numpy arrays that define the x and y axes of a grid. For example:
13 Answers
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