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SQRT2.HLP
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1989-01-24
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803b
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28 lines
Name: SQRT2.ASM
Type: Assembler Macro
Version: 1.0
Last Change: 26-Jan-87
Description: Square Root Approximation (10 bit accuracy)
This will take the square root of a number by polynomial approximation.
sqrt(x)=-.1985987*x*x+.8803385*x+.3175231
This polynomial will give approximately 10 significant bits of accuracy.
This is valid for: .5<= x < 1.0
The input value is put into x0, the output value is returned in register
A. Register R1 initially points to the coefficients in y memory in the
order:a1,a2,a0.
R1
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v
y:.8803385,-.1985987,.3185231
a1 a2 a0
Benchmarks for this macro is 4 cycles, 4 instructions.
The library program SQRT2T demonstrates how to use the SQRT2 macro.