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How to export DataTable to Excel
...
Try simple code, to convert DataTable to excel file as csv:
var lines = new List<string>();
string[] columnNames = dataTable.Columns
.Cast<DataColumn>()
.Select(column => column.ColumnName)
.ToArray();
var header = ...
postgresql - sql - count of `true` values
...his works:
SELECT count(*) AS total
, sum(myCol::int) AS countTrue --convert Boolean to Integer
FROM yourTable
;
or better (to avoid :: and use standard SQL syntax):
SELECT count(*) AS total
, sum(CAST(myCol AS int)) AS countTrue --convert Boolean to Integer
FROM yourTable
;
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Algorithm to get the excel-like column name of a number
I'm working on a script that generate some Excel documents and I need to convert a number into its column name equivalent. For example:
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How to properly check if std::function is empty in C++11?
... an empty lambda doesn't really make sense. Behind the scenes the compiler converts a lambda expression into a struct (or class) definition, with the variables you capture stored as data members of this struct. A public function call operator is also defined, which is what allows you to invoke the l...
How can I unit test Arduino code?
...ctical testing on your ultimate target
hardware. I am trying to make a point about optimizing your
development feedback cycle by eliminating your target hardware from
your most mundane and frequent tests. The units under test are assumed
to be much smaller than the whole project.
The purpo...
Default template arguments for function templates
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On Windows, with all versions of Visual Studio you can convert this error (C4519) to a warning or disable it like so:
#ifdef _MSC_VER
#pragma warning(1 : 4519) // convert error C4519 to warning
// #pragma warning(disable : 4519) // disable error C4519
#endif
See more details ...
Type converting slices of interfaces
I'm curious why Go does't implicitly convert []T to []interface{} when it will implicitly convert T to interface{} . Is there something non-trivial about this conversion that I'm missing?
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Fastest way to determine if an integer's square root is an integer
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Wow! I'll try to convert this to Java and do a comparison, as well as an accuracy check on the results. I'll let you know what I find.
– Kip
Jan 12 '09 at 21:47
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Convert decimal to hexadecimal in UNIX shell script
In a UNIX shell script, what can I use to convert decimal numbers into hexadecimal? I thought od would do the trick, but it's not realizing I'm feeding it ASCII representations of numbers.
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Convert character to ASCII code in JavaScript
How can I convert a character to its ASCII code using JavaScript?
10 Answers
10
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