2
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The command

NestList[Cos, 1.5, 10]

produces the list:

{0.750313, 0.731476, 0.74419, 0.735637, 0.741403, 0.737522,
 0.740137, 0.738376, 0.739563, 0.738763, 0.739302}

What is an easy way to have each number in the list have 10 significant digits?

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1
  • $\begingroup$ They already have 16 significant digits; they are just not all printed. Try InputForm, or otherwise change the print precision in Preferences. I wouldn't recommend jumping to arbitrary precision numbers without a good reason, nor reassigning precision using SetPrecision without a very good understanding of what it does. $\endgroup$ Commented Jan 13, 2015 at 12:11

1 Answer 1

5
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Try the following,

N[NestList[Cos, 15/10, 10], 10]

{*
{1.500000000,0.07073720167,0.9974991672,0.5424049923,0.8564697089,0.6551088018,
0.7929816458,0.7017241683,0.7637303113,0.7222610821,0.7503128857}
*}

SetAccuracy[NestList[Cos, 1.5, 10], 10];
SetPrecision[NestList[Cos, 1.5, 10], 10];


NumberForm[NestList[Cos, 1.5, 10], {10, 10}]

{*
{1.5000000000,0.0707372017,0.9974991672,0.5424049923,0.8564697089,
0.6551088018,0.7929816458,0.7017241683,0.7637303113,0.7222610821,0.7503128857}
*}

Edit
With F1 or ?? you can find more information:

?? SetAccuracy

enter image description here

?? Accuracy

enter image description here

?? SetPrecision

enter image description here

?? Precision

enter image description here

?? NumberForm

enter image description here

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3
  • $\begingroup$ Thanks. I've learned a lot from your answer. $\endgroup$
    – David
    Commented Jan 12, 2015 at 14:49
  • $\begingroup$ May I ask "What is the difference between precision and accuracy?" $\endgroup$
    – David
    Commented Jan 12, 2015 at 14:56
  • $\begingroup$ @David, My Pleasure, see my Edit. $\endgroup$
    – user9660
    Commented Jan 12, 2015 at 15:10

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