KimonoMyHouse

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9 years, 205 days

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These are questions asked by KimonoMyHouse

Hello people,

 

I've been working with a list of [x,y,z] elements, where the x and y are positions, and z is the value at given x y. I wish to be able to plot the results so that they look like this

Plot of points

 link:http://imgur.com/t6fEHee

I made the above plot using the following code

surfdata(points[1],dimension=2,colorscheme=["Orange","MediumBlue"])

where points[1] is a list of lists of points.

Glad that i was succesful, i tried to apply this method to a must larger number of points, only to be met by the following error

Error, (in makePlotFromLargeFNASet) assigning to a long list, please use Arrays

So, i made it so that points[1] became an array instead of a list of lists. When trying to apply surfdata now, using the exact same line as above, the plot is not 2D with colors as the 3rd dimension, but only returns a 3D plot as if dimension=3. It is endlessly frustrating, since there doesn't seem to be any sense to the error, and i cannot find an answer to why it does so. Any help would be appreciated!

 

Thanks in advance,

Mehdi

 

EDIT: I have uploaded the worksheet and the two files that i use on the following link:

http://www.filedropper.com/plotscript

Hey people,

 

I am trying to get the following code to run, but it keeps returning an error about too many arguments

 

restart:with(plots):with(PDEtools):
alpha_const := 0.5:gamma_const := 2.5: D1 := 0.05: D2 := 0.002:
A := diff_table(a(x,t)):B := diff_table(b(x,t)):
Selkov[1] := A[t] = 1 - A[]*B[]^(gamma_const) + D1*A[x,x]:
Selkov[2] := B[t] = alpha_const * ( A[]*B[]^(gamma_const) - B[]) + D2 * B[x,x]:

bc[1] := D[1](a)(0,t)=0: bc[2] := D[1](b)(0,t)=0: bc[3] := D[1](a)(4*Pi,t) = 0: bc[4]:=D[1](b)(4*Pi,t)=0:

ic[1] := eval(A[],t=0)=a_0:ic[2] := eval(B[],t=0)=b_0:
case1 := eval(ic,[a_0=1,b_0=1]):
case2 := eval(ic, [a_0=piecewise((x<2*Pi+1) and (x>2*Pi-1), 0.99, 1), b_0=piecewise((x<2*Pi+1) and (x>2*Pi-1), 0.99, 1)]):

Case1Default := pdsolve({Selkov[1],Selkov[2]},{bc[1],bc[2],bc[3],bc[4],case1[1],case1[2]},numerical);


Error, (in pdsolve/sys) too many arguments; some or all of the following are wrong: [{a(x, t), b(x, t)}, {a(x, 0) = 1, b(x, 0) = 1, (D[1](a))(0, t) = 0, (D[1](a))(4*Pi, t) = 0, (D[1](b))(0, t) = 0, (D[1](b))(4*Pi, t) = 0}, numerical]

 

My code worked just earlier today, and now it wont. If i try to run pdsolve({Selkov[1],Selkov[2]}) it says that there is an error with general case of floats. 

 

You help is greatly appreciated!

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