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 2020-01-02 05:42:36 -0600 received badge ● Popular Question (source) 2017-08-11 11:51:11 -0600 received badge ● Famous Question (source) 2017-04-10 21:45:57 -0600 received badge ● Famous Question (source) 2016-10-20 00:35:01 -0600 received badge ● Taxonomist 2016-08-16 06:17:55 -0600 received badge ● Notable Question (source) 2016-08-16 06:16:17 -0600 received badge ● Popular Question (source) 2016-04-13 18:28:11 -0600 received badge ● Notable Question (source) 2016-04-13 18:28:11 -0600 received badge ● Popular Question (source) 2014-08-18 17:12:18 -0600 received badge ● Student (source) 2014-08-18 16:37:57 -0600 received badge ● Famous Question (source) 2014-08-18 16:30:40 -0600 received badge ● Popular Question (source) 2014-08-18 16:30:40 -0600 received badge ● Notable Question (source) 2014-08-18 16:30:40 -0600 received badge ● Famous Question (source) 2014-08-18 16:30:28 -0600 asked a question Bitwise NOT Operator for Sage? 0b1000 & 0b1001 (AND) 0b1000 | 0b1001 (OR) 0b1000 ^^ 0b1001 (XOR) All of these work as bitwise operators on the command line -- but how do I do bitwise NOT? 2014-06-25 20:04:31 -0600 received badge ● Notable Question (source) 2014-06-22 06:41:38 -0600 received badge ● Popular Question (source) 2013-11-29 09:56:18 -0600 asked a question Moving the decimal point I would like to have my answer expressed not in scientific notation... how would I do this? For example, instead of reporting 2.12345e5, I just want 212345 Thanks! 2013-10-02 10:11:16 -0600 marked best answer How do I assign solutions of an equation to a variable? You can use the method .rhs() or .right_hand_side() as follows: sage: a = solve(1-z-z^2==0,z)[0].rhs() sage: a -1/2*sqrt(5) - 1/2  2013-10-02 08:10:03 -0600 asked a question How do I assign solutions of an equation to a variable? a = solve(1-z-z^2==0,z)[0] has the result of a being 'z=-1/2*sqrt(5)-1/2' But I would like to have just a = '-1/2*sqrt(5)-1/2' How do I convert the expression to a number? Thanks! 2013-09-04 06:55:44 -0600 asked a question 3dplot of modulus of complex function Even though abs(x+I*y) should always be real... I get the following error: plot3d(abs(x+I*y),(x,-5,5),(y,-5,5)) ERROR: unable to coerce to a real number 2013-08-27 07:15:14 -0600 commented answer Plotting Sequence of Points Thank you - that works. 2013-08-27 06:43:54 -0600 asked a question Plotting Sequence of Points How do I plot the sequence {1/n} for n = 1 to 100 in Sage? I browsed plot?, but didn't see it as an option, or I didn't know what it was called. 2013-07-25 04:45:59 -0600 marked best answer Binomial in a Summation Sum is working only in a symbolic ring. So you can convert your integers to the symbolic ring as follows: sum(binomial(SR(5),k),k,0,SR(5))  You can also use the add command: add([binomial(5,k) for k in [0..5]])  2013-07-25 04:45:58 -0600 received badge ● Supporter (source) 2013-07-25 03:28:50 -0600 received badge ● Editor (source) 2013-07-25 03:28:29 -0600 asked a question Binomial in a Summation sage: var('k') k sage: sum(binomial(5,k),k,0,5) I get an error "cannot convert k to int" But if instead I try something like sum(binomial(n,k),k,0,n), everything is just fine. Anyone know how I can get around this? 2013-07-10 04:47:01 -0600 received badge ● Scholar (source) 2013-07-10 04:47:01 -0600 marked best answer Summing with Euler_phi Error I guess this is because euler_phi does not accept symbolic argument sage: var('z') sage: euler_phi(z) Traceback (most recent call last): ... PariError: not an integer argument in an arithmetic function (18)  Nevertheless, you can do sage: sum((euler_phi(k)/k)*log(1/(1-2*z^k)) for k in xrange(2,5)) 1/2*log(-1/(2*z^4 - 1)) + 2/3*log(-1/(2*z^3 - 1)) + 1/2*log(-1/(2*z^2 - 1))  2013-07-10 04:29:53 -0600 asked a question Summing with Euler_phi Error New to sage, having some trouble with summation. z, k both declared as variables. sum((euler_phi(k)/k)log(1/(1-2z^k)),k,2,5) Error: not an integer argument in an arithmetic function (18) If I change it to euler_phi(5)/5 it's fine.