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What is :: (double colon) in Python when subscripting sequences?
...
TL;DR
This visual example will show you how to a neatly select elements in a NumPy Matrix (2 dimensional array) in a pretty entertaining way (I promise). Step 2 below illustrate the usage of that "double colons" :: in question.
(Caution: this is a NumPy array specific example with...
How can I easily convert DataReader to List? [duplicate]
... writing an extension method for this:
public static IEnumerable<T> Select<T>(this IDataReader reader,
Func<IDataReader, T> projection)
{
while (reader.Read())
{
yield return projection(reader);
}
}
You can then use LINQ...
Export Postgresql table data using pgAdmin
...
Just right click on a table and select "backup". The popup will show various options, including "Format", select "plain" and you get plain SQL.
pgAdmin is just using pg_dump to create the dump, also when you want plain SQL.
It uses something like this: ...
Better way of incrementing build number?
...ersion number (only) when a project is archived for export.
# @usage
# 1. Select: your Target in Xcode
# 2. Select: Build Phases Tab
# 3. Select: Add Build Phase -> Add Run Script
# 4. Paste code below in to new "Run Script" section
# 5. Check the checkbox "Run script only when installing"
# 6. ...
How do I display a text file content in CMD?
...e lines in the text file simply read the file using Get-Content, then have Select-Object pick out the last five items/lines for you:
Get-Content c:\scripts\test.txt | Select-Object -last 5
Source: Using the Get-Content Cmdlet
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Difference between JOIN and INNER JOIN
...nal,
or you can specify CROSS JOIN.
OR
For an inner join, the syntax is:
SELECT ...
FROM TableA
[INNER] JOIN TableB
(in other words, the "INNER" keyword is optional - results are the same
with or without it)
share
...
Create batches in linq
... int maxItems)
{
return items.Select((item, inx) => new { item, inx })
.GroupBy(x => x.inx / maxItems)
.Select(g => g.Select(x => x.item));
}
}
and the usage would be:
List<int> list = new L...
Case conventions on element names?
...inent examples:
<a>1</a><b>1</b>
<xsl:value-of select="a+b"/>
outputs 2, as expected
<a>1</a><b>1</b>
<xsl:value-of select="a-b"/>
DOES NOT ERROR, BUT OUTPUTS NOTHING AT ALL
In the above code, you must put at least one space before a su...
LINQ to Entities does not recognize the method
...re(iv => alm_x_suc.Exists(axs => axs.almacen == iv.LOCNCODE.Trim())).Select(iv => iv.ITEMNMBR.Trim()).ToList();
this was the exactly error:
System.NotSupportedException: 'LINQ to Entities does not recognize the method 'Boolean Exists(System.Predicate`1[conector_gp.Models.almacenes_por...
How to make ng-repeat filter out duplicate results
... unique filter) and use it directly in the ng-options (or ng-repeat).
<select ng-model="orderProp" ng-options="place.category for place in places | unique:'category'">
<option value="0">Default</option>
// unique options from the categories
</select>
...