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Question: "evalf" output depends upon style of input?

Question:"evalf" output depends upon style of input?

Scot Gould 747 Maple 2020
2dmath evalf
June 22 2020
1

In preparing to sample problems, I came across this difference in an output depending upon the input type: 2d Input vs. Maple Input. Is there a typo on my part?


 

> 

restart; kernelopts(version); Digits

`Maple 2020.1, X86 64 WINDOWS, Jun 10 2020, Build ID 1474787`

  

10

 (1)

Very happy with the output of the following line:

> 

x := evalf[30](3.0^1.2)

3.73719281884655197790004100992

 (2)

 

But I'm confused about the output of the next line. Is it a limit to the calculation or a display problem?

> 

a := evalf[30](3.0^(1.2))

3.737192819

 (3)

 

and yet this next output looks fine:

> 

b := evalf[30]( exp( 1.2 * ln(3)))

3.73719281884655197790004100989

 (4)

 

Fortunately, there appears to be no difference between x and b:

> 

evalf[30](x-b)

0.3e-28

 (5)

 

But these next  lines suggest there is an actual limit in the calculation of a.

> 

evalf[30](a-b)

0.15344802209995899011e-9

 (6)
> 

evalf[30](a - b);

0.15344802209995899011e-9

 (7)

Note - when Digits is set to 30, the calculation difference between x and a disappears.

> 

``


 

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