Re: [sage-support] Re: Global variables called in a function

No. You can try def f(): var('whatever') f() print whatever Nothing to do with the fact that 't' was globally available before. By design the function var: - creates a new symbolic variable (*not* a Python variable) - makes it available in the global namespace as a Python variable

Re: [sage-support] Re: Global variables called in a function

Thanks I guess I don't understand the difference between a python variable and a symbolic variable. I know that var is part of Sage but not defined in python. I also know that the variables created inside a sage procedure using SR.var are local, but ones created by var are not. So inside of

Re: [sage-support] Re: Global variables called in a function

Thanks I guess I don't understand the difference between a python variable and a symbolic variable. I know that var is part of Sage but not defined in python. I also know that the variables created inside a sage procedure using SR.var are local, but ones created by var are not. So inside of

Re: [sage-support] Re: Global variables called in a function

To avoid confusion use "symbol" instead of "symbolic variable". A Python variable is a variable in the sense of programming https://en.wikipedia.org/wiki/Variable_%28computer_science%29 A symbol represents a mathematical variable as in https://en.wikipedia.org/wiki/Variable_%28mathematics%29

Re: [sage-support] Re: Global variables called in a function

On 2015-12-22 01:11, Carl Eberhart wrote: Thanks I guess I don't understand the difference between a python variable and a symbolic variable. A symbolic variable is a symbol or letter in the mathematical sense. It is like the "x" appearing in mathematical formulas like sin(x)^2 + cos(x)^2 ==

Re: [sage-support] Re: Global variables called in a function

On 2015-12-21 16:38, Carl Eberhart wrote: I admit I don't understand what is happening in the following snippit: def f(): t=var('t') t=5 a=2*t return a Solution: never use var() in a function. If you do need a symbolic variable in a function (note that you don't in the

Re: [sage-support] Re: Global variables called in a function

On Monday, December 21, 2015, Carl Eberhart wrote: > I admit I don't understand what is happening in the following snippit: > > def f(): > t=var('t') > t=5 > a=2*t > return a > t=3;t;f();t > 3 > 10 > t > > This was executed in a sagews cell > I think that

Re: [sage-support] Re: Global variables called in a function

I admit I don't understand what is happening in the following snippit: def f(): t=var('t') t=5 a=2*t return a t=3;t;f();t 3 10 t This was executed in a sagews cell I think that the t which is referenced in f should be a local variable. However the value of t outside of f is

Re: [sage-support] Re: Global variables called in a function

Ah. Thanks very much for that clarification. Actually, my snippet illustrates the dilemma I was in. t already has a value outside of f executing f changes the value of t outside of f that is what I would expect to happen if t were declared global in f, but I thought t was local in f I still love

[sage-support] Re: Global variables called in a function

sage: x = this is x sage: y = this is y sage: z = this is z sage: def f(): :     print x :     y = new value :     print y :     global z :     z = new value :     print z : sage: f() this is x new value new value sage: x, y, z ('this is x', 'this is

Re: [sage-support] Re: Global variables called in a function

On Thu, Sep 30, 2010 at 3:07 AM, Walker ebwal...@gmail.com wrote: sage: x = this is x sage: y = this is y sage: z = this is z sage: def f(): :     print x :     y = new value :     print y :     global z :     z = new value :     print z : sage: f() this

[sage-support] Re: Global variables called in a function

Hi Walker! On 29 Sep., 16:42, Walker ebwal...@gmail.com wrote: ... My question is: is there a way to make Sage not creating a global variable but assigning directly the global one? This is actually a Python question. It would of course be very dangerous if variables defined outside a function

[sage-support] Re: Global variables called in a function

It seems it has solved my issue, many thanks all of you; I'll attach a snipped of code next time. I knew Sage is based on Pyton, but what I don't know is where the first ends and the second begins, so I usually think my issue is a Sage's one... Anyway, thank you: it was helpful. -- To post to

Re: [sage-support] Re: Global variables called in a function

On Wed, Sep 29, 2010 at 8:18 AM, Simon King simon.k...@nuigalway.ie wrote: Hi Walker! On 29 Sep., 16:42, Walker ebwal...@gmail.com wrote: ... My question is: is there a way to make Sage not creating a global variable but assigning directly the global one? This is actually a Python question.