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Quickly reading very large tables as dataframes
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# sqldf as on SO
f <- file("test.csv")
system.time(SQLf <- sqldf("select * from f", dbname = tempfile(), file.format = list(header = T, row.names = F)))
## user system elapsed
## 10.21 0.47 10.73
ff / ffdf
require(ff)
system.time(FFDF <- read.csv.ffdf(file="test.csv",nro...
Enabling auto layout in iOS 6 while remaining backwards compatible with iOS 5
...tolayout can be enabled or disabled on each .storyboard or .xib file. Just select the particular file and modify the "Use Autolayout" property using the File inspector in Xcode:
Using autolayout enabled interface files with the deployment target set to an iOS version prior to 6.0 results in compi...
C# Pass Lambda Expression as Method Parameter
....Where(predicate.Compile()) //here compile your clausuly
select x;
newList.ToList();//return a new list
}
Calling method
Method(v => v.Equals(1));
You can do the same in their class, see this is example.
public string Name {get;set;}
public static List...
Check if a dialog is displayed with Espresso
... correct button in the dialog.
UiObject button = uiDevice.findObject(new UiSelector().text("ButtonText"));
if (button.exists() && button.isEnabled()) {
button.click();
}
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How to print the current Stack Trace in .NET without any exception?
...oint where you want to see the stack trace.
Right-click the breakpoint and select "Actions..." in VS2015. In VS2010, select "When Hit...", then enable "Print a message".
Make sure "Continue execution" is selected.
Type in some text you would like to print out.
Add $CALLSTACK wherever you want to se...
Keyboard shortcut for Jump to Previous View Location (Navigate back/forward) in IntelliJ IDEA
...me Intel grafics driver shorcuts on windows. Right click the desktop -> select Screen Resolution -> Click Advanced settings -> Click the vendor tab "Intel(R) ..." -> Hit the graphics properties or similar button -> Select Options and Support tab -> Disable Hotkey functionality.
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How can I trigger a JavaScript event click
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To repeat the click more than once: Add an ID to the element to uniquely select it:
<a href="#" target="_blank" id="my-link" onclick="javascript:Test('Test');">Google Chrome</a>
and call the .click() method in your JavaScript code via a for loop:
var link = document.getElementById(...
Is there a way to create multiline comments in Python?
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In any case, your text editor should also be able to easily comment-out a selected region (by placing a # in front of each line individually). If not, switch to a text editor that does.
Programming in Python without certain text editing features can be a painful experience. Finding the right edito...
R command for setting working directory to source file location in Rstudio
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Worked for me in RStudio v1.0.143 on Windows 10. If you select "Source on save", it will work just fine (you can print out the detected directory with "cat"). If you select the lines then execute them, then the result is null.
– Contango
Jun ...
How to edit one specific row in Microsoft SQL Server Management Studio 2008?
...rver Management Studio 2008/2012/2014/2016
Step 1: Right button mouse > Select "Edit Top 200 Rows"
Step 2: Navigate to Query Designer > Pane > SQL (Shortcut: Ctrl+3)
Step 3: Modify the query
Step 4: Right button mouse > Select "Execute SQL" (Shortcut: Ctrl+R)
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