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Understanding keystore, certificates and alias
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The dev site suggests using the same certificate for all your apps. So does this mean, as long as I'm using the same keystore, I can use any alias with any password and it won't mess up updates, as it's just a reference? The actual keystore is the important part?
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What is the difference between related SQLite data-types like INT, INTEGER, SMALLINT and TINYINT?
When creating a table in SQLite3, I get confused when confronted with all the possible datatypes which imply similar contents, so could anyone tell me the difference between the following data-types?
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How do I get the width and height of a HTML5 canvas?
...n the canvas element, the default 300x150 size will be returned. To dynamically get the correct width and height use the following code:
const canvasW = canvas.getBoundingClientRect().width;
const canvasH = canvas.getBoundingClientRect().height;
Or using the shorter object destructuring syntax:
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Printing the value of a variable in SQL Developer
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Make server output on First of all
SET SERVEROUTPUT on then
Go to the DBMS Output window (View->DBMS Output)
then Press Ctrl+N for connecting server
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Cleaning `Inf` values from an R dataframe
...ption 1
Use the fact that a data.frame is a list of columns, then use do.call to recreate a data.frame.
do.call(data.frame,lapply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal copying.
DT <- data.table(dat)...
Determine the data types of a data frame's columns
...ation as a vector (i.e. you don't need it to do something else programmatically later), just use str(foo).
In both cases foo would be replaced with the name of your data frame.
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How do you copy the contents of an array to a std::vector in C++ without looping?
... later processing. Since I don't know how many times my function will be called before it is time to process the data, I need a dynamic storage structure, so I chose a std::vector . I don't want to have to do the standard loop to push_back all the values individually, it would be nice if I coul...
Why should C++ programmers minimize use of 'new'?
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There are two widely-used memory allocation techniques: automatic allocation and dynamic allocation. Commonly, there is a corresponding region of memory for each: the stack and the heap.
Stack
The stack always allocates memory in a sequential fashion. It c...
How do I search within an array of hashes by hash values in ruby?
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You're looking for Enumerable#select (also called find_all):
@fathers.select {|father| father["age"] > 35 }
# => [ { "age" => 40, "father" => "Bob" },
# { "age" => 50, "father" => "Batman" } ]
Per the documentation, it "returns an array contai...
Pushing a local branch up to GitHub
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If you are really lazy, you can push all local branches by simply using
git push --all
--all
Push all branches (i.e. refs under refs/heads/); cannot be used with
other <refspec>.
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