What is the difference between algorithm and logarithm

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You do not currently have access to this article. Download all slides. Sign in Don't already have an Oxford Academic account? You could not be signed in. But you probably already think logarithmically about numbers.

The number is 10 times as big as the number 10, but it only has one more digit. The number 1,, is , times as big as 10, but it only has five more digits. The number of digits a number has grows logarithmically. And thinking about numbers also shows why logarithms can be useful for displaying data. Can you imagine if every time you wrote the number 1,, you had to write down a million tally marks? Log scales can be useful because some types of human perception are logarithmic.

In the case of sound, we perceive a conversation in a noisy room 60 dB to be just a bit louder than a conversation in a quiet room 50 dB. Yet the sound pressure level of voices in the noisy room might be 10 times higher. Another reason to use a log scale is that it allows scientists to show data easily. It would be hard to fit the 10 million lines on a sheet of graph paper that would be needed to plot the differences from a quiet whisper 30 decibels to the sound of a jackhammer decibels.

In C. But maybe that change is not a bad thing, because algorism can also refer to the Arabic numerals themselves which we use in modern mathematics, and it can also refer to the method of computing with those numerals, plus zero i. So it's really kind of nice to have a separate word that means what we now mean by algorithm. It's just that that word is not logarithm.

So,in this fictitious example, because the results of the algorithm are expressed as a logarithm to base 10, a rank of 10 has ten times as great a total numerical value as a rank of 9 does. Of course, if the base is different from 10, then the pagerank numbers could represent numerical values that are either much closer together, or even much farther apart!

Even before the problematic Panda, some SEO experts had begun a voluntary, somewhat anecdotal experiment to help figure out the logarithm base that Google uses. But, even if they did or do ever figure that out, it would have limited value unless they also knew the relative or weighted value of the give-or-take-a-few factors in the algorithm.

So there you have it. An algorithm is a formula, a series of steps that will solve a mathematical problem. A logarithm is a number that expresses the exponent of a base to arrive at some given number.

A logarithm can be part of an algorithm, in some instances. And, since certain steps need to be followed in calculating a logarithm, I suppose we can also say that there may be an algorithm for figuring out a logarithm.

What's the difference. Pretend you are asked the question on an elevator, and would receive a million dollars, if the people understood it. Thank you, Hugh Williamson and BlissfulWriter! I love seeing mathematical relations between all kinds of things in the world around us - but I know that I don't always or perhaps don't often understand what I see.

I just know that earthquake magnitude scale is a logarithic scale. And that Google has an algorithm. I think our world is much more mathematical than we realize and your Hub makes the point nicely. I don't know how well a math themed Hub does on HP, but I for one enjoyed this. I have to laugh at myself when I realize I feel so amazed that anyone could have a base 12 monetary system I like feet and yards, pints, quarts, pecks, etc. I'm glad you brought up the binary system and computers.

I have considered writing a sort of philosophical ramble on the type of thought process that reduces everything to only two choices, yes and no. Break something down into its simplest form, then - if done in proper sequence - all kinds of complexity can be achieved.

You have done a great job explaining both of these mathematical concepts. It is not so long ago when we in Ireland and England used base 12 for our money and I remember as boy when we went metric.

I was always intrigued at how every number could be expressed so differently simply by changing its base. When discussing logarithms, exponents often lead to confusion. These properties are the idea behind the slide rule.

Adding two numbers can be viewed as joining two lengths together and measuring their combined length. Multiplication is not so easily done. However, if the numbers are first converted to the lengths of their logarithms, then those lengths can be added and the inverse logarithm of the resulting length gives the answer for the multiplication this is simply logarithm property 1.

A slide rule measures the length of the logarithm for the numbers, lets you slide bars representing these lengths to add up the total length, and finally converts this total length to the correct numeric answer by taking the inverse of the logarithm for the result. Contact Us Privacy License « 3.