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How to count items in a Go map?
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Use len(m). From http://golang.org/ref/spec#Length_and_capacity
len(s) string type string length in bytes
[n]T, *[n]T array length (== n)
[]T slice length
map[K]T map length (number of defined keys)
c...
Passing an integer by reference in Python
...n Python, assignment (=) takes whatever object is the result of the right hand side and binds it to whatever is on the left hand side *(or passes it to the appropriate function).
Understanding this, we can see why there is no way to change the value of an immutable object inside a function -- you c...
Python: List vs Dict for look up table
...f you don't need to associate values, use sets.
Memory
Both dictionaries and sets use hashing and they use much more memory than only for object storage. According to A.M. Kuchling in Beautiful Code, the implementation tries to keep the hash 2/3 full, so you might waste quite some memory.
If you...
Python: One Try Multiple Except
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If for example you have to convert multiple versions of a data structure to a new structure, when updating versions of code for example, you can nest the try..excepts.
– Rolf of Saxony
Dec 4 '15 at 14:00
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What is the difference between Scope_Identity(), Identity(), @@Identity, and Ident_Current()?
I know Scope_Identity() , Identity() , @@Identity , and Ident_Current() all get the value of the identity column, but I would love to know the difference.
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select into in mysql
I am a MSSQL user and now I am converting my database to MySQL. I am writing the following query in MySQL:
2 Answers
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ASP.NET MVC Ajax Error handling
How do I handle exceptions thrown in a controller when jquery ajax calls an action?
6 Answers
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Executing Batch File in C#
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This should work. You could try to dump out the contents of the output and error streams in order to find out what's happening:
static void ExecuteCommand(string command)
{
int exitCode;
ProcessStartInfo processInfo;
Process process;
processInfo = new ProcessStartInfo("cmd.exe"...
Read Excel File in Python
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A somewhat late answer, but with pandas it is possible to get directly a column of an excel file:
import pandas
import xlrd
df = pandas.read_excel('sample.xls')
#print the column names
print df.columns
#get the values for a given column
values = df['Arm_id']...
Test if element is present using Selenium WebDriver?
... that is not what I want, because it can be that an element is not present and that is okay, that is not a fail of the test, so an exception can not be the solution.
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