# Julia Surface or Non-Square Heatmap Plots with Spesific Function
**URL:** https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826
**Category:** General Usage
**Tags:** plotting
**Created:** [April 23, 2023, 6:32pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826 "2023-04-23T18:32:11Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@Umut\_Can\_Turhan](https://discourse.julialang.org/u/Umut_Can_Turhan)
#### Post date: [April 23, 2023, 6:32pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826/1 "2023-04-23T18:32:11Z")
Hi! I have some coordinates points (non-grid or non-square):
Each scatter points have x values:
74-element Vector{Any}:
13.0
2.0
59.5
55.0
22.0
57.5
21.0
28.0
100.5
35.0
64.0
34.5
23.0
⋮
85.5
83.0
66.0
27.5
93.0
61.0
69.5
76.0
69.0
16.5
110.0
106.0
and y values:
74-element Vector{Any}:
0.0
0.0
0.8660254037844386
1.7320508075688772
1.7320508075688772
2.598076211353316
3.4641016151377544
3.4641016151377544
4.330127018922193
5.196152422706632
5.196152422706632
6.06217782649107
6.928203230275509
⋮
0.8660254037844386
1.7320508075688772
1.7320508075688772
2.598076211353316
3.4641016151377544
3.4641016151377544
4.330127018922193
5.196152422706632
5.196152422706632
6.06217782649107
6.928203230275509
6.928203230275509
And also, I have specific returning values of the function (or depth) according to each of these scatter points. The returning values of the function:
192-element Vector{Float64}:
0.01026092990158084
0.009416080348692598
0.012298969043634662
0.013916606632920811
0.013167799244802145
0.014012477885523053
0.012621339395756463
0.010104323450266985
0.009989015887079901
0.0079859912194493
0.00572453020447633
0.006531826655798263
0.008111449480620387
⋮
0.00899896427675875
0.006889139181813508
0.007463671690395065
0.007420493510579368
0.008208763532334944
0.0071625911073200915
0.007557154510503339
0.00962856024830995
0.007751236255200042
0.007921710076830122
0.009087707129757795
0.009139276992711463
My function depends on x and y coordinates. For example;
MyFunction(x\_co[6],y\_co[6]) = 0.00899896427675875
So, I want to plot z values (or depth or returning values of the MyFunction()) on this 2D scatter plot via a non-square heatmap (due to the structure of scatter points) or surface.
When I try to plot as a surface, I encounter the error:
\*\*\* IDENTICAL DATA POINTS.
NDP = 74 IP1 = 28 IP2 = 44 XD=21 YD=6.9282
ERROR DETECTED IN ROUTINE IDTANG.
---
### Author:  [@gdalle](https://discourse.julialang.org/u/gdalle)
#### Post date: [April 23, 2023, 9:02pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826/2 "2023-04-23T21:02:27Z")
Hi! Can you provide us with a reproducible example?
As a first remark, your vectors for x and y coordinates have element type `Any`, which suggests you might have defined them using something like `x = []` before pushing into them. It works, but your code will be more efficient if you specify the element type beforehand, like so: `x = Float64[]`.
---
### Author:  [@Umut\_Can\_Turhan](https://discourse.julialang.org/u/Umut_Can_Turhan)
#### Post date: [April 24, 2023, 5:39pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826/3 "2023-04-24T17:39:59Z")
Let’s keep it simple. I have basic following code:
```julia
x = Int64[1,2,3,4,5]
y = Int64[1,2,3,4,5]
function Myfun(x,y)
return x*y
end
surface(x,y,Myfun())
```
My coordinate list like this:
```julia
[0,0
0,1
0,2
0,3
.
.
.
5,5]
```
I want to plot density values (returning values of Myfun(x,y) in this case) in each coordinates points. I don’t have range to plot basic 3D surface plot like this:
```julia
f(x, y) = sin(x) + cos(y)
surface(0:0.1:10, 0:0.1:10, f)
```
Instead of, I have spesific x and y values to plot surface plot. How can I solve my problem?
---
### Author:  [@kellertuer](https://discourse.julialang.org/u/kellertuer)
#### Post date: [April 24, 2023, 6:21pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826/4 "2023-04-24T18:21:41Z")
Could you maybe extend the example to code that we can easily run?
See [Please read: make it easier to help you](https://discourse.julialang.org/t/please-read-make-it-easier-to-help-you/14757).
In your smaller example here
1. Which package are you using? `Plots.jl`?
2. `surface(x,y,Myfun())` does not work, since `MyFun` does not work for zero parameters as it is called here
But if you have a list of points, say
```julia
using Plots
x = [1,1,2,2,3,3]
y = [1,2,2,3,3,4]
```
and have computed
```julia
z = f.(x,y)
```
then
```julia
surface(x,y,z)
```
(from Plots.jl) works just as intended
But note that if you have a point twice, like in the following where I repeated the first
```julia
x = [1,1,1,2,2,3,3]
y = [1,1,2,2,3,3,4]
z = f.(x,y)
```
you get
```julia
julia> surface(x,y,z)
*** IDENTICAL DATA POINTS.
NDP = 7 IP1 = 1 IP2 = 2 XD=1 YD=1
ERROR DETECTED IN ROUTINE IDTANG.
```
Since if a point appears double (in my example the first and the second are both `[1,1]`) the plot does not know what to do (here even\_though\_ the `z` value is the same.
As far as I see the result, `IP1, IP2` tell you the inices (for me nodes 1 and 2, for you 28 and 44) and the `x` and `y` value that is repeated (for me again both are 1 for you the point `(21,6.9282)`.
In scatter, I think, it will just plot the blue dot twice, but for the surface, you have to avoid duplicates.
I hope I guessed your code correct – and welcome to the Julia forum 🙂
---
### Author:  [@empet](https://discourse.julialang.org/u/empet)
#### Post date: [April 24, 2023, 7:06pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826/5 "2023-04-24T19:06:46Z")
Change the type of your data as @gdalle pointed out. Then this code should work (incidentally, last week I experimented with the new version of DelaunayTriangulation.jl):
```julia
using DelaunayTriangulation, PlotlyJS
function get_surface(x::T,y::T,z::T) where T<:Real
pts=[[xe, ye] for (xe, ye) in zip(x,y)]
tri = triangulate(pts)
#PlotlyJS mesh3d works with triangle ids starting from 0:
mtriangles= mapreduce(permutedims, vcat, [[id for id in t] for t in tri.triangles]) .-1
surf = mesh3d(x=x, y=y, z=z,
i=mtriangles[:, 1],
j=mtriangles[:, 2],
k=mtriangles[:, 3],
intensity=z,
colorscale=colors.plasma,
colorbar_thickness=24,
)
layout = Layout(width=500, height=500,
scene_camera_eye=attr(x=1.65, y=1.65, z=1))
pl = Plot(surf, layout)
end
pl=get_surface(x,y,z)
display(pl)
```
---
### Author:  [@Umut\_Can\_Turhan](https://discourse.julialang.org/u/Umut_Can_Turhan)
#### Post date: [April 24, 2023, 7:14pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826/6 "2023-04-24T19:14:35Z")
All of my problems are that:
```julia
# Please, don't care what are the function arguments and their's values.
# Just focus x and y coordinates and the plot section.
Nx = 2;Ny = 2
# A any given function to get x coordinates.
x_coordinates = get_sites(Nx, Ny, a1_vec, a2_vec, Basis)[4]
# Recreate the array to avoid the 'OffsetArray' function. It maybe prevents the plotting process (?)
x = Float64[]
for i in x_coordinates
push!(x, i)
end
println("My x-values: \n", x)
# A any given function to get y coordinates.
y_coordinates = get_sites(Nx, Ny, a1_vec, a2_vec, Basis)[5]
# Recreate the array to avoid the 'OffsetArray' function. It maybe prevents the plotting process (?)
y = Float64[]
for i in y_coordinates
push!(y, i)
end
println("\n My y-values: \n", y)
# !
my_coordinate_list = hcat(x, y) # there is no repeated (x,y) pairs !
println("\n My coordinate or (x,y) pairs: \n",my_coordinate_list)
# My Function
function MyFun(x,y)
return x*y
end
# Get returning value for specific (x,y) pair
println("\n The output of my function: \n",MyFun(x[1],y[1]))
# Plot section
using Plots
surface(x, y, MyFun(x, y))
```
The outputs of my code:
```julia
My x-values:
[0.0, 1.0, 0.5, 1.0, 2.0, 1.5, 2.0, 3.0, 2.5, 3.0, 4.0, 3.5]
My y-values:
[0.0, 0.0, 0.8660254037844386, 1.7320508075688772, 1.7320508075688772, 2.598076211353316, 0.0, 0.0, 0.8660254037844386, 1.7320508075688772, 1.7320508075688772, 2.598076211353316]
My coordinate or (x,y) pairs:
[0.0 0.0; 1.0 0.0; 0.5 0.8660254037844386; 1.0 1.7320508075688772; 2.0 1.7320508075688772; 1.5 2.598076211353316; 2.0 0.0; 3.0 0.0; 2.5 0.8660254037844386; 3.0 1.7320508075688772; 4.0 1.7320508075688772; 3.5 2.598076211353316]
The output of my function:
0.0
```
In this case, I want to plot the surface of z values according to each (x,y) pair.
---
### Author:  [@kellertuer](https://discourse.julialang.org/u/kellertuer)
#### Post date: [April 24, 2023, 7:24pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826/7 "2023-04-24T19:24:53Z")
> [@Umut\_Can\_Turhan](#):
>
> `x_coordinates = get_sites(Nx, Ny, a1_vec, a2_vec, Basis)[4]`
I am sorry I can not run your code since the function `get_sites` is not defined (in your example if I run the code lines in the order you provide them). The same holds for `a1_vec` and `a2_vec` and `Basis`.
So I can again just take an educated guess…
If I use your print and define
```julia
x = [0.0, 1.0, 0.5, 1.0, 2.0, 1.5, 2.0, 3.0, 2.5, 3.0, 4.0, 3.5]
y = [0.0, 0.0, 0.8660254037844386, 1.7320508075688772, 1.7320508075688772, 2.598076211353316, 0.0, 0.0, 0.8660254037844386, 1.7320508075688772, 1.7320508075688772, 2.598076211353316]
```
Then I can also define
```julia
function MyFun(x,y)
return x*y
end
```
But your call to `MyFun(x, y)` does not work since `*` is not defined for vectors. If I do instead
```julia
z = MyFun.(x,y)
using Plots
surface(x,y,z)
```
(Note the `.` in the first line since I want to apply `MyFun` to _every pair_ of `x` and `y`!)
This works just fine.
---
### Author:  [@Umut\_Can\_Turhan](https://discourse.julialang.org/u/Umut_Can_Turhan)
#### Post date: [April 24, 2023, 8:02pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826/8 "2023-04-24T20:02:46Z")
Thank you so much ^^. My problem was the usage of `surface(x,y,MyFun(x,y))` instead of `surface(x,y,MyFun.(x,y))`. So can I ask an additional question? How can I set the top view of the surface with the camera=(Int,Int) argument?
---
### Author:  [@kellertuer](https://discourse.julialang.org/u/kellertuer)
#### Post date: [April 24, 2023, 8:19pm UTC](https://discourse.julialang.org/t/julia-surface-or-non-square-heatmap-plots-with-spesific-function/97826/9 "2023-04-24T20:19:29Z")
You‘re welcome.
I am not sure about `camera=`, where do you have that from? Ah maybe from GR? It might be that the first is rotation in x,y, the second elevation angle? To me
```julia
surface(x,y,z; camera = (0,90))
```
seems right, but might again just be a guess, since I could find no docs.