[sage-edu] integer, tostring, length?
Sorry, silly question: OK, I know I've done this in Sage before, but I can't remember for the life of me how. I'm writing a program that computes large integers and tests for primality. What I'd like to do is print out the integer and how many digits it has. I seem to remember having to convert the integer to a string and then find its length() or size(). Could someone please remind me how this works? TIA, A. Jorge Garcia http://calcpage.tripod.com Teacher & Professor Applied Mathematics, Physics & Computer Science Baldwin Senior High School & Nassau Community College --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "sage-edu" group. To post to this group, send email to sage-edu@googlegroups.com To unsubscribe from this group, send email to sage-edu+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-edu?hl=en -~--~~~~--~~--~--~---
[sage-edu] Re: integer, tostring, length?
Do you mean this? sage: n = 1234567890123456789 sage: len(str(n)) 19 On Sat, Sep 19, 2009 at 10:14 AM, wrote: > > Sorry, silly question: > > OK, I know I've done this in Sage before, but I can't remember for the > life of me how. > > I'm writing a program that computes large integers and tests for > primality. What I'd like to do is print out the integer and how many > digits it has. I seem to remember having to convert the integer to a > string and then find its length() or size(). > > Could someone please remind me how this works? > > TIA, > A. Jorge Garcia > http://calcpage.tripod.com > > Teacher & Professor > Applied Mathematics, Physics & Computer Science > Baldwin Senior High School & Nassau Community College > > > > > > > --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "sage-edu" group. To post to this group, send email to sage-edu@googlegroups.com To unsubscribe from this group, send email to sage-edu+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-edu?hl=en -~--~~~~--~~--~--~---
[sage-edu] Re: integer, tostring, length?
Yes, that was it! Thank you! How easy it is to forget syntax in one environment when using another. I was teaching java all day yesterday and I just couldn't remember the equivalent in Sage! BTW, I had worksheets in sagenb online where I saved a lot of 'notes to self' whenever I figured out something like this so I could look it up later as needed. Well those worksheets are now blank and I don't know why! HTH, A. Jorge Garcia http://calcpage.tripod.com Teacher & Professor Applied Mathematics, Physics & Computer Science Baldwin Senior High School & Nassau Community College --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "sage-edu" group. To post to this group, send email to sage-edu@googlegroups.com To unsubscribe from this group, send email to sage-edu+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-edu?hl=en -~--~~~~--~~--~--~---
[sage-edu] Re: integer, tostring, length?
On Sat, 19 Sep 2009 at 10:25AM -0400, David Joyner wrote: > Do you mean this? > > sage: n = 1234567890123456789 > sage: len(str(n)) > 19 There's also n.ndigits(), which I think directly returns the number of digits without doing any conversion to a string. You can even specify different bases, so if n = 8, you get 1 for base 10, and 3 for base 2. You can also put in really large bases: sage: n = 1025 sage: n.ndigits(1024) 2 Dan -- --- Dan Drake - http://mathsci.kaist.ac.kr/~drake --- signature.asc Description: Digital signature
