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Add regression line equation and R^2 on graph

... Here is one solution # GET EQUATION AND R-SQUARED AS STRING # SOURCE: https://groups.google.com/forum/#!topic/ggplot2/1TgH-kG5XMA lm_eqn <- function(df){ m <- lm(y ~ x, df); eq <- substitute(italic(y) == a + b %.% italic(x)*","~~italic(r)^2~"="~r2, l...
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How to run a method every X seconds

...nits.SECONDS) .flatMap(new Function<Long, ObservableSource<String>>() { @Override public ObservableSource<String> apply(@NonNull Long aLong) throws Exception { return getDataObservable(); //Where you pull your data ...
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What is an efficient way to implement a singleton pattern in Java? [closed]

...erializable Singleton public enum Elvis { INSTANCE; private final String[] favoriteSongs = { "Hound Dog", "Heartbreak Hotel" }; public void printFavorites() { System.out.println(Arrays.toString(favoriteSongs)); } } Edit: An online portion of "Effective Java" says:...
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How do I add a simple onClick event handler to a canvas element?

...hello world!')"; // does nothing, even with clicking You are assigning a string to the onClick property of elem. elem.onClick = function() { alert('hello world!'); }; // does nothing JavaScript is case sensitive. The onclick property is the archaic method of attaching event handlers. It only al...
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Find and copy files

... find -iname '*.mp3' -mtime -1 -exec cp {} /home/my_path/ \; is there anything wrong with this command ? it's not working – mrid Feb 20 '18 at 5:13 2 ...
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C# - Keyword usage virtual+override vs. new

...onsole.WriteLine("B::bar()"); } } class Program { static int Main(string[] args) { B b = new B(); A a = b; a.foo(); // Prints A::foo b.foo(); // Prints B::foo a.bar(); // Prints B::bar b.bar(); // Prints B::bar return 0; } } ...
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Python: List vs Dict for look up table

...st and use binary search. This is O(log n), and is likely to be slower for strings, impossible for objects which do not have a natural ordering. share | improve this answer | ...
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Open files in 'rt' and 'wt' modes

...d binary file modes (on all platforms). In text mode, read returns Unicode strings. In binary mode, read returns a bytes instance. If you want to write Python 2 code with forwards compatibility in mind, you can use io.open rather than the standard open to get the Python 3 behavior (with unicode vers...
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Serialize form data to JSON [duplicate]

... You can do this: function onSubmit( form ){ var data = JSON.stringify( $(form).serializeArray() ); // <----------- console.log( data ); return false; //don't submit } <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> ...
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how to generate migration to make references polymorphic

...ass AddImageableToProducts < ActiveRecord::Migration def up change_table :products do |t| t.references :imageable, polymorphic: true end end def down change_table :products do |t| t.remove_references :imageable, polymorphic: true end end end ...