I have been reading for the last hour about different ways to take an nth root in sage. I am having trouble finding a way to do so for very large numbers.

Any help would be much appreciated. I have tried ^(1/n) and pow and a number of others.

  • $\begingroup$ x^(1/n), x**(1/n), or pow(x,1/n) should all work. If the problem is that you want a concrete number rather than a symbolic expression, try n(x^(1/n)) to find the approximate numerical value of an expression. You might also want to run tutorial() to open a browser window with the tutorial. $\endgroup$ – András Salamon Oct 10 '16 at 2:28
  • $\begingroup$ When I do those it just appends ^(1/5) for example to my number... It doesn't actually do the operation. $\endgroup$ – MathIsHard Oct 10 '16 at 2:32
  • $\begingroup$ This is my number 383359376317228026832765614031101780857214373741934853796883469684751393959423303934031779306976105234618634914722122231966050161090557311139688754390702005669975825514220776140658553598335180339644221202109745240693646681489614040361698983885974381266138822986136754230956173498395067036601233601299698337833849969027885834924082799260330843401454066113756946449729494314541583444719025620597701816509274146453 $\endgroup$ – MathIsHard Oct 10 '16 at 2:34
  • $\begingroup$ This is M^(1/5) $\endgroup$ – MathIsHard Oct 10 '16 at 2:34
  • 1
    $\begingroup$ @ryBear - yes, I just try to help cross-ref for people searching later. $\endgroup$ – kcrisman Oct 10 '16 at 2:50

If you are looking for a numerical approximation, there are several routes open to you. Here are two.

  • You can approximate after taking it with e.g. a.n(digits=100), like here
  • You can use a decimal point like 383. instead of 383 and then do the root

More advanced options include setting a "real field" with a certain accuracy like R=RealField(1000) and using that ...


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