[sage-support] Re: Numerical integration and parametic curves

2014-09-10 Thread Volker Braun
The s = var('s') is not necessary (the argument s inside the functions shadows it). As for the original question, IMHO there is a learning opportunity here. Numerical integration is powerful, but it doesn't give you symbolic answers. Even if you make the integration bound a symbolic variable.

[sage-support] Re: Numerical integration and parametic curves

2014-09-10 Thread Hal Snyder
Appreciate the pointers. Plot statement in prior posting could also be parametric_plot((g,h),(-pi,pi)) which has a nicer default aspect ratio. BTW there is sage code for Cornu spiral in the wikipedia article, Euler spiral http://en.wikipedia.org/wiki/Euler_spiral. On Wednesday, September

[sage-support] Very basic questions - Number of digits in floats

2014-09-10 Thread Christophe Bal
Hello. I would to do two thinks. 1. Know the number of decimal digits that Sage uses in a program. 2. Choose the number of decimal digits displayed. Sorry for this unformal question. Christophe BAL -- You received this message because you are subscribed to the Google Groups

Re: [sage-support] Very basic questions - Number of digits in floats

2014-09-10 Thread Jeroen Demeyer
On 2014-09-10 15:06, Christophe Bal wrote: Hello. I would to do two thinks. 1. Know the number of decimal digits that Sage uses in a program. 2. Choose the number of decimal digits displayed. I believe the recommended way to choose the precision is to do: RR = RealField(1000)# 1000

Re: [sage-support] Very basic questions - Number of digits in floats

2014-09-10 Thread Jeroen Demeyer
On 2014-09-10 15:06, Christophe Bal wrote: 1. Know the number of decimal digits that Sage uses in a program. The default is 53 bits, which is 15 to 16 decimal digits. -- You received this message because you are subscribed to the Google Groups sage-support group. To unsubscribe from this

Re: [sage-support] Very basic questions - Number of digits in floats

2014-09-10 Thread William A Stein
On Wed, Sep 10, 2014 at 8:09 AM, Jeroen Demeyer jdeme...@cage.ugent.be wrote: On 2014-09-10 15:06, Christophe Bal wrote: Hello. I would to do two thinks. 1. Know the number of decimal digits that Sage uses in a program. 2. Choose the number of decimal digits displayed. I believe the

Re: [sage-support] Very basic questions - Number of digits in floats

2014-09-10 Thread Jeroen Demeyer
On 2014-09-10 17:18, William A Stein wrote: RR is pre-defined to be RealField(53), and overwriting that might cause confusion. How that? Nothing in Sage uses the RR global (and if it does, that's a bug). -- You received this message because you are subscribed to the Google Groups

[sage-support] Re: Very basic questions - Number of digits in floats

2014-09-10 Thread Dima Pasechnik
On 2014-09-10, Jeroen Demeyer jdeme...@cage.ugent.be wrote: On 2014-09-10 17:18, William A Stein wrote: RR is pre-defined to be RealField(53), and overwriting that might cause confusion. How that? Nothing in Sage uses the RR global (and if it does, that's a bug). All over the place in

[sage-support] sage symbolic error

2014-09-10 Thread William A Stein
Hi, Bill Page reported this issue, which I'm copying here to the sage-support list, in the hopes somebody will look into it: sage: var('k, l') sage: f = real(cosh(sqrt(1/2*k-1/2*sqrt(k^2+4l sage: g = f.substitute_expression(imag_part(k)==0,imag_part(l)==0,real_part(k)==k,real_part(l)==l) #

[sage-support] Re: sage symbolic error

2014-09-10 Thread Nils Bruin
On Wednesday, September 10, 2014 11:02:05 AM UTC-7, Stein William wrote: Hi, Bill Page reported this issue, which I'm copying here to the sage-support list, in the hopes somebody will look into it: sage: var('k, l') sage: f = real(cosh(sqrt(1/2*k-1/2*sqrt(k^2+4l The problem is

Re: [sage-support] Very basic questions - Number of digits in floats

2014-09-10 Thread Christophe Bal
Thanks for all !!! Christophe BAL 2014-09-10 17:38 GMT+02:00 William A Stein wst...@uw.edu: On Wed, Sep 10, 2014 at 8:24 AM, Jeroen Demeyer jdeme...@cage.ugent.be wrote: On 2014-09-10 17:18, William A Stein wrote: RR is pre-defined to be RealField(53), and overwriting that might cause