scottfontenot
6/26/2017 - 12:33 AM

Unit 2-Lesson 4: Arrays and Loops (additional material)

Unit 2-Lesson 4: Arrays and Loops (additional material)

sort()Method.md
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This method sorts an array in place. In place means that this method sorts the original array;

It does not copy the array, sort it, and then return the sorted copy.

If you pass no arguments to .sort(), it will alphabetically sort the list by default

string example
sorting ordinal numbers

slice()Method_creates a new array from an existing one.md
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.slice(begin, end)

you can use negative values for the begin parameter in order to select the last n numbers of an array.

from begin to end(end not included)

orginal array is not modified

slice method
return a portion of an existing array
<a href="https://jsbin.com/kisenuc/1/edit?js,console,output" target="_blank>slice removing last 2 from array

shift_method_Like.pop(), but removes and returns the first element of a list.md
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remove first element from arrary and return
removing element from array

push_method_o add an item to the end of an array.md
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general example
adding elements to array
merging two arrays

pop_method_remove the final item from an array. It also returns the discarded item.md
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remove last element and return element
more examples
another example

math()method_used to generate a new array of items by applying the same function to each item in the original array.md
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<a href="https://jsbin.com/kahisix/1/edit?js,console,output" target="_blank>map method
map method to double values in an array

length_property.md
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iterating over an Arrays
iterating over an Arrays
example of an Array length
shortening an array

forEach()_Like .map().md
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this method applies a function to each item in a collection, but it does not return an array of transformed elements

example
better example
converting from For Loop to .forEach

Javascript_methods.md
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Javascript_methods

creating an array
accessing an array
<a href="https://jsbin.com/jesecuz/1/edit?js,console,output>Map to produce HTML elements

.reduce()method.md
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This is useful for aggregating array data. This method iterates over the array while maintaining an accumulation object. This object is returned inside the reduce function and is passed into the subsequent iteration.

reduce method
another reduce method

.find()method.md
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This method is used to find a single item in an array.

find method
find an object in an array by one of its properties

.filter()method.md
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This method is used to take one array of items, and make a new one that contains only items that a filtering function returns true for.

filter
filter long words
filtering out all small values