How to get Matlab to return answers with ten-digit accuracy?

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Noob 2020-9-17

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评论： Noob 2020-9-18

Hi,

Answers returned by Matlab (e.g. from the ode45 solver, or from the wrapTo2Pi function that maps accumulating angles to [0, 2pi] ) seem to be within four digits of accuracy; that is, it rounds to four digits after the decimal place.

I'm currently studying convergence and root-finding and would like ten-digit accuracy -- so, a bit beyond the standard function tolerance of 1e-6 or 1e-7.

How can I get Matlab answers with ten-digit accuracy?

Thanks,

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回答（2 个）

Mario Malic 2020-9-17

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编辑：Mario Malic 2020-9-17

在 MATLAB Online 中打开

Write this on start of your script

format long

If you're reading the values from the workspace, find tab 'View' and under 'Format', click 'Long Fixed Decimal'.

Edit: this only changes displayed output, see James' answer.

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Noob 2020-9-18

Hi James,

Ok, will do - and thanks so much for your help.

Noob 2020-9-18

Hi Walter,

Ok, thanks so much - have a good night.

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William 2020-9-17

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The answers returned by Matlab actually have the full available precision, but for display purposes they are printed in the command window with a much smaller precision. You can change this default behavior by typing 'format long' or 'format longEng' in the command window.