plotting Jacobian elliptic function

Question

How can I plot bellow function in MATHEMATICA, MATLAB, or MAPLE?

Here $cn$ is the Jacobi elliptic function:

$$ f(x)=0.7951556995+0.0048443005cn^2(0.4831042546x,0.1118800243)$$

score 1 · Accepted Answer · answered Jan 16 '20 at 18:29

1

In Mathematica:

Plot[0.7951556995 + 0.0048443005 JacobiCN[0.4831042546 x,0.1118800243]^2,{x,0,5}]

answered Jan 16 '20 at 18:29

caverac

19,345

Beat me to it by about 11 seconds! – David G. Stork Jan 16 '20 at 18:30
@DavidG.Stork I'm pretty sure you have a prettier version =) Please post it, we all can learn from it – caverac Jan 16 '20 at 18:31
Nope... basically the same... – David G. Stork Jan 16 '20 at 18:31
@DavidG.Stork The basic form is a little complicated. It is from cnoidal waves in plasma. – sepide shirazi Jan 17 '20 at 17:48
@sepideshirazi: A request: Ask the minimum relevant question. Did you really need to state all those constants to 10 significant figures? Of course not. – David G. Stork Jan 17 '20 at 17:55
Sorry, the basic problem was a physics case,not a math one, it was from a complicated dynamics of a fluid system. Posting the real problem is not suitable here. – sepide shirazi Jan 17 '20 at 18:35
But you would get essentially the same information from asking about plotting $1+2 cn^2(3x,4)$. You could put in the actual values of the parameters yourself. – Robert Israel Jan 17 '20 at 19:40
Yes, you're right and thank you. – sepide shirazi Jan 18 '20 at 09:01

score 1 · Answer 2 · answered Jan 16 '20 at 19:11

In Maple the function is JacobiCN, but the parameter is different: Maple uses the modulus $k$ where Mathematica uses the amplitude $k^2$. So to get caverac's plot in Maple, you would use

plot(0.7951556995 + 0.0048443005*JacobiCN(0.4831042546*x, sqrt(0.1118800243))^2, x=0..5);

plotting Jacobian elliptic function

2 Answers2