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2.5. Implementing the genetic code
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Remember we were designing our translation algorithm and since we are a bit lazy, we decided to make the hypothesis that there was the adequate function forimplementing the genetic code. It's now time to see this lookupfunction but just before that come back on this condition herewhich is a bit more complex than the first attempt in writing the algorithm. Here you see the keyword OR, itmeans that this condition is true if this one is true or thisone is true or this one is true. Why do we need this morecomplex condition? Imagine our sequence and there washere the last triplet we translated. Now we increase our index fromthat position to that one. In the first version of the algorithm, we made the hypothesis that there was a star symbol hereand that was the end of the sequence but imagine that we havehere for example C and T and the star symbol is here. So the condition test is the starsymbol here or here or here and then we have to stop. In either of the three cases:that one, that one or that one. That's why we had thismore complex condition. OK. So lookup genetic code is afunction that we have to write now, so for that we come back to the implementation of the genetic code. For the matter of convenience,for this function, we now see the genetic code as an array again,array of 64 rows because there are 64 combinations of threeletters but four columns.
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