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6 Cards in this Set
- Front
- Back
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Arrays |
uses [] indexing - indicies start at 0 minus counts backwords [-1] PICKAXE p68 |
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array[1,3] |
returns new array [start,count] anArray = [1,2,3,4,5,6] anotherArray = anArray[2,3] anotherArray = [3,4,5] PICKAXE p68 |
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array[2..5] array[2...5] |
2 dots = just me 3 dots = them and me anArray = [1,2,3,4,5,6] anotherArray = anArray[2..5] anotherArray = [3,4] Array2 = anArray[2...5] Array2 = anArray[2,3,4,5] PICKAXE p69 |
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setting elemets in array |
a = [1,2,3,4,5,6] a[2] = L a = [1,2,L,4,5,6] a[8] = M # any inbetween values generated are nil a = [1,2,L,4,5,6,nil,nil,M] a[6] = [11,12] #can make 2d array a = [1,2,L,4,5,6,[11,12],nil,M] bonus points for using arrayposition and count to set new elemnts in(see pickaxe) PICKAXE p69 |
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.push .pop .unshit. shift |
.push, add elements to end of array .pop, remove elements from the end of the array, useful for stacking things .unshift add elemnts to front .shift remove elemnt from front queue = [] queue.push "red" queue.push "green" puts queue.shift puts queue.shift produces: red green PICKAXEp68 |
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.first .last |
return the n indices from front or back, withour removing them from the array(still in order) a=[1,2,3,4,5,6,7,8,9] a.first(3)=[1,2,3] a.last(3)=[7,8,9] PICKAXEp70 |
