ASKSAGE: Sage Q&A Forum - RSS feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Sat, 05 Sep 2020 11:14:41 +0200I'm searching to perform this multivariate limit (correctly)https://ask.sagemath.org/question/53309/im-searching-to-perform-this-multivariate-limit-correctly/ I'm searching to perform this kind of limit (without restricting and executing the limit to a variable):
$$
\lim_{(x, y)\to(0, 0)}\frac{x^3y}{x^6+y^2}
$$
In the documentation I didn't find a multivariate limit function..Teo7Sat, 05 Sep 2020 11:14:41 +0200https://ask.sagemath.org/question/53309/help on using chain rule in Sagehttps://ask.sagemath.org/question/36673/help-on-using-chain-rule-in-sage/Does anyone have any tips for using Sage to take derivatives of functions of many variables?
For example, if I define
```w(x,y) = x^2 + y^2``` (say)
and then if I suppose that ```x``` and ```y``` depend on an independent variable ```t```, the chain rule applies for finding ```w.diff(t)```. The only way I found to do this in Sage is
```var('t')```
```x(t) = cos(t)``` (say)
```y(t) = sin(t)```
```w(x,y) = x^2 + y^2```
```w.diff(t)```
But this isn't really using the chain rule. If I instead try
```var('x,y')```
```(define w again)```
```(define x and y again)```
```w.diff(t)```
```Out: (x,y) |--> 0```
Apparently it thinks the derivative is zero because it still thinks ```x``` and ```y``` are two independent variables where they appear in ```w```, even though you get
```x```
```Out: t |--> cos(t)```
and similarly for ```y```. Any suggestions? Thanks.
lefthandstanderMon, 20 Feb 2017 08:25:01 +0100https://ask.sagemath.org/question/36673/Multivariate Taylor Serieshttps://ask.sagemath.org/question/9783/multivariate-taylor-series/Hi. I know `f.taylor(x, x_0, n)` would generate an n-order Taylor approximation of f around x_0 for a function of a single variable. How can I do this for multiple variables? I know Maxima can handle it. How do I do this in sage?yktulaThu, 07 Feb 2013 18:13:48 +0100https://ask.sagemath.org/question/9783/