ShmoopTube

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And here's your shmoop du jour brought to you by multi-dimensional [Spacecraft opens up in space and cube character appears]

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arrays they're not just a sci-fi alien weapon people...What is the value of Q

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and here are your potential answers..... well quick visualize an array

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of eight elements do it got it? yeah pretty simple it's a little like a [Man thinking of 8 elements]

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number line but with data sitting on it that and to refer to any element you can

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call it by its index what if you want another row of data well sure you could

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make a whole new separate array but that's little clunky this is more of a

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job for a two-dimensional array add an extra set of brackets and well off we go [array with added set of brackets]

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we can reference anything in this array by using two indices horizontal and

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vertical or clever names x and y want to get wild I'll we can keep going on to [Men in a boxing ring ready to fight]

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three dimensional arrays are totally doable and turn our square into a

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cube and again we'd be using the arrays three indices so we can reference [Cube with an array]

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elements anywhere along its three axes so now we have a three dimensional array

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full of data sounds very futuristic already but we can go further than that [Man hurdling over arrays]

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what would a fourth dimension be like where would you put it? easy! well right

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next to it just like a complaint from your physicist friend all right if a

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one-dimensional array gave us a number line 2D gave us a square and 3D

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gives us a cube then 4D is a number line made of cubes did we just blow your [Explosion occurs]

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mind all right and a 5d array well you guessed it a grid made of cubes.. 6D? a

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cube made of cubes.. 7D a number line made of a cube made of cubes you can see

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where this is headed into infinity well the Java language specification states [Buzz flys away and java specification book appears]

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that you could theoretically have infinite dimensions but the Java Virtual

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Machine the thing that actually excutes the code sets a limit of 250 five [Laptop with 255 dimensions on the screen]

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dimensions thankfully for our brains the need for that many dimensions doesn't

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come up all that often in fact an array of more than three dimensions is [Mans head opens and arrays enter inside]

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downright rare and this question is asking us what the length of a certain

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two-dimensional array would be logically speaking

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since we're dealing with a 2d array it'd makes sense to multiply width x height

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like measuring a rectangle like 12 times 10 but that's not how the length function

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works in Java it returns a simple integer based on the length of a single

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dimension in this case the first dimension because we didn't specify a [Java code line circled]

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deeper one that said the answer was right in front of our faces the entire

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time it's just as well.

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