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Data sets often contain comments that explain the data format or contain the license and usage terms. You usually want to ignore these lines when you read in the DataFrame. The readtable function assumes that comment lines begin with the '#' character. However, your file may use comment marks like ...

Method overriding is the way of using polymorphism between classes. if one class is inherited from another, the former (sub class) can override the latter's (super class's) methods, and change the implementation. this is used where the super class defines the more general implementation of the meth...

a = [1, 2, 3, 4, 5] # steps through the list backwards (step=-1) b = a[::-1] # built-in list method to reverse 'a' a.reverse() if a = b: print(True) print(b) # Output: # True # [5, 4, 3, 2, 1]

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Query store can be enabled on database by using the following command: ALTER DATABASE tpch SET QUERY_STORE = ON SQL Server/Azure SQL Database will collect information about executed queries and provide information in sys.query_store views: sys.query_store_query sys.query_store_query_text sy...

The following query will return informationa about qeries, their plans and average statistics regarding their duration, CPU time, physical and logical io reads. SELECT Txt.query_text_id, Txt.query_sql_text, Pl.plan_id, avg_duration, avg_cpu_time, avg_physical_io_reads, avg_logica...

If you want to remove some query or query plan from query store, you can use the following commands: EXEC sp_query_store_remove_query 4; EXEC sp_query_store_remove_plan 3; Parameters for these stored procedures are query/plan id retrieved from system views. You can also just remove execution ...

SQL Query optimizer will choose the baes possible plan that he can find for some query. If you can find some plan that works optimally for some query, you can force QO to always use that plan using the following stored procedure: EXEC sp_query_store_unforce_plan @query_id, @plan_id From this poi...

ObservableCollection is a collection of type T like List<T> which means that it holds objects of type T. From documentation we read that : ObservableCollectionrepresents a dynamic data collection that provides notifications when items get added, removed, or when the entire list is refres...

LINQ extension methods on IEnumerable<T> take actual methods1, whether anonymous methods: //C# Func<int,bool> fn = x => x > 3; var list = new List<int>() {1,2,3,4,5,6}; var query = list.Where(fn); 'VB.NET Dim fn = Function(x As Integer) x > 3 Dim list = New List F...

$scheme = 'https' $url_format = '{0}://example.vertigion.com/foos?{1}' $qs_data = @{ 'foo1'='bar1'; 'foo2'= 'complex;/?:@&=+$, bar''"'; 'complex;/?:@&=+$, foo''"'='bar2'; } [System.Collections.ArrayList] $qs_array = @() foreach ($qs in $qs_data.GetEnumerator()...

$scheme = 'https' $url_format = '{0}://example.vertigion.com/foos?{1}' $qs_data = @{ 'foo1'='bar1'; 'foo2'= 'complex;/?:@&=+$, bar''"'; 'complex;/?:@&=+$, foo''"'='bar2'; } [System.Collections.ArrayList] $qs_array = @() foreach ($qs in $qs_data.GetEnumerator()...

List all the node versions installed nvm ls v4.5.0 v6.7.0 Run command using any node installed version nvm run 4.5.0 --version or nvm exec 4.5.0 node --version Running node v4.5.0 (npm v2.15.9) v4.5.0 nvm run 6.7.0 --version or nvm exec 6.7.0 node --version Running node v6.7.0...

This is the Cypher, Neo4j's query language. In many ways, Cypher is similar to SQL if you are familiar with it, except SQL refers to items stored in a table while Cypher refers to items stored in a graph. First, we should start out by learning how to create a graph and add relationships, since tha...

Once you've connected to your mailbox, you'll want to take a look inside. The first useful command is imap_list. The first parameter is the resource you acquired from imap_open, the second is your mailbox string and the third is a fuzzy search string (* is used to match any pattern). $folders = ima...

Before getting started, make sure you have the latest Azure PowerShell installed. Once installed, start an Azure PowerShell session from your machine. First, you'll need to log in and authenticate to Windows Azure. Add-AzureRmAccount You'll receive a dialog box asking for your Azure credentials...

roslaunch is an important tool that manages the start and stop of ROS nodes. It takes one or more "*.launch" files as arguments. For this example, I will refer to the following (as asked in this question), so how can we execute those commands consecutively & automatically : roscd ste...

let bodies = (contact.bodyA.categoryBitMask <= contact.bodyB.categoryBitMask) ? (A:contact.bodyA,B:contact.bodyB) : (A:contact.bodyB,B:contact.bodyA) switch (bodies.A.categoryBitMask,bodies.B.categoryBitMask) { case let (a, _) where (a && superPower): //All we care about is i...

Objective-C First add the Social Framework to the XCode project. Import the #import "Social/Social.h" class to the required ViewController Twitter with text, image and link //- - To Share text on twitter - - if([SLComposeViewController isAvailableForServiceType:SLServiceTypeTwitter]) ...

// myString is "hi" NSMutableString *reversedString = [NSMutableString string]; NSInteger charIndex = [myString length]; while (charIndex > 0) { charIndex--; NSRange subStrRange = NSMakeRange(charIndex, 1); [reversedString appendString:[myString substringWithRange:subS...