The post “How can I convert a list of strings into sympy variables?” discusses how to generate SymPy symbols from a list of strings. My question is what steps are needed to use these symbols x, y and z in SymPy calculations? I tried something along the lines but I get the error “NameError: n…
Tag: sympy
Sympy gives a residual value when trying to solve the logistics equation
If I try solving the logistics differential equation in Sympy I get a residual value (10^(-13)) which prevents sympy from getting the correct values for the initial coditions. If I run this code: import sympy as sp I get: How can one get rid of these residuals in the solution? Answer Either don’t use Fl…
How to solve the ‘mul objective has no attribute ‘cos’ ‘
How to solve the multi object problem? If I input 2, the expected result should be 2*cos(2*x). Answer Your code contains a few misconceptions. One problem is an important general programming rule: try to use different variable names for variables with different meanings. So, x shouldn’t be assigned a fl…
Sympy – Arithmetic and geometric sequence in recursive form
I would like to define arithmetic and geometric sequences in recursive form like Un+1 = Un + r (u0 n>0) Un+1 = qUn (u0 n>0) In Sympy, one can define in closed form an arithmetic sequence like this : How can I define (not solve) this sequence in recursive form (Un+1 = Un + r) ? Answer You’ll need t…
Displaying sympy equations on matplot
Now I want to display the sympy equation “eq” on the plot. I have seen many methods to display the same equation using tex commands, but I specifically want to display the sympy eq. Thanks in advance Answer You could use sympy’s latex() function like this:
symbolic complex expression simplification
Although my question is related to a specific problem, I would like to approach it in more general terms. I would like to simplify a fractional complex expression obtained by multiplying symbolic matrices using the sympy package. What I get is a fraction with real parameters and many complex exponential terms…
Is it possible to assign a symbol of partial derivative via symbols() in SymPy?
I would like to symbolically represent one of variables as a partial derivative like: dF_dx = symbols(‘dF/dx’) so that display(dF_dx) would show it as: Is there a way to do it? The official reference is not very clear to a newbie. Thank you. Answer _print_Derivative currently decides based on requ…
Is there a way to do fraction in sympy
I am trying to do fraction using sympy, I know sympy is supports symbolic but can it be done with old fraction, please know that I want it to be display it as unevaluatedexpr here is my code. Answer
Sympy multiplies answer changing it and making it wrong
I am trying to find the inverse of a matrix, however, sympy always multiplies the final answer by 4, thereby making the answer wrong. This multiplication also happens when I use the factor function. Here is the matrix I want to change And here is the “wrong” answer it gives The true answer is the …
How to use sympy to algebraically solve a two sided equation
I’d like to use sympy to solve he following equation in terms of x, g, and w. Here’s what I thought I should code But this seems to be trying to solve for a numerical answer. Answer You can create a 2-sided equation with Eq: When you say that you want to solve “in terms of x, g and w”