Julia>1.2 + 0.12 1.3199999999999998

Excellent news, it’s within floating point precision of the true result. And welcome to Julia!

Floating-point arithmetic | Accuracy problems The fact that floating-point numbers cannot accurately represent all real numbers, and that floating-point operations cannot accurately represent true arithmetic operations, leads to many surprising situations. This is related to the finite pr…

…and just to be clear: this happens with any programming language that uses floating point arithmetic… and that pretty much covers them all.

Also you may want to consider https://github.com/JuliaMath/Decimals.jl?files=1

Julia should probably cover this up by rounding the printed results, this behaviour can be pretty confusing for beginners.

Thanks very much. But I am worried that the error accumulation is serious.

you can use BigFloat with arbitrary precision to check if your algorithm looses precision.

To the best of my understanding it is as serious as in other languages. If you need exact results, use the decimal package mentioned above

[image] bernhard: If you need exact results, use the decimal package mentioned above Decimals.jl (and similar packages like the more full-featured DecFP.jl ) only eliminate rounding errors in converting human decimal inputs into their computer representations. Arithmetic operations can still…

what is "1.2+0.21" in Julia?

General Usage

DNF August 9, 2018, 1:28pm 6

This is the post you should read to get a quick overview of floating point issues: PSA: floating-point arithmetic

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what is "1.2+0.21" in Julia?

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