How do calculators calculate logarithms

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Create a free Team What is Teams? Learn more. What algorithm is used by computers to calculate logarithms? Ask Question. Asked 10 years, 2 months ago. Active 7 months ago. Viewed 52k times. So the question is: what algorithm is used by computers to calculate logarithms? Joshua Schwartz 5 4 4 bronze badges. Show 2 more comments. Active Oldest Votes.

For intel IA64, apparently they use Taylor series combined with a table. Aryabhata Aryabhata I searched on Knuth's Art of computer programming, where he suggested another method. Perhaps it would make sense to quote some relevant parts here? I can't access the second link too. Add a comment. However, usually, the number of terms in the numerator and denominator are about the same as the number of terms in an equivalent Maclaurin series.

Then there is an extra division, which can be expensive on some processors. I generally avoided them, but it is definitely worth mentioning them.

Walther PDF describes a unified CORDIC algorithm that can be used for multiplication, division, sin, cos, tan, arctan, sinh, cosh, tanh, arctanh, ln, exp and square root. Walther link was broken. Show 3 more comments. Try also these books: J. Press the "Log" button on your calculator.

The number you immediately see is the exponent for the original number you entered. Assuming the base number is 10 which it will always be on a graphing or scientific calculator , you have to multiply 10 by itself the number of times you see onscreen to reach your original number. Check your work. Entering "" into your calculator and pressing "Log" will result in the number "3" appearing on screen.

This means that you have to multiply your base number of 10 three times to reach " Stephen Lilley is a freelance writer who hopes to one day make a career writing for film and television. His articles have appeared on a variety of websites.

How to Find Cube Root in Ti How to Use a Calculator for Trigonometry. How to Calculate Arctan. How to Do Powers in Math.