# PyError, RuntimeError('Error in qhull Delaunay triangulation calculation: singular input

**URL:** <https://discourse.julialang.org/t/pyerror-runtimeerror-error-in-qhull-delaunay-triangulation-calculation-singular-input/19088>\
**Category:** General Usage\
**Created:** [December 29, 2018, 12:24pm UTC](https://discourse.julialang.org/t/pyerror-runtimeerror-error-in-qhull-delaunay-triangulation-calculation-singular-input/19088 "2018-12-29T12:24:47Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![yasirhassan](https://avatars.discourse-cdn.com/v4/letter/y/2bfe46/32.png) [@yasirhassan](https://discourse.julialang.org/u/yasirhassan)\
**Post date:** [December 29, 2018, 12:24pm UTC](https://discourse.julialang.org/t/pyerror-runtimeerror-error-in-qhull-delaunay-triangulation-calculation-singular-input/19088/1 "2018-12-29T12:24:47Z")

</div>

trying to run code:  
using Plots  
pyplot()  
x=y= range( 10, stop = 81, length = 12)  
r= sqrt.(x.^2 + y.^2)  
z = sin.(r) ./r ;  
Plots.plot(x,y,z, st= :surface, camera = (-30,30))

throws following error:  
Error showing value of type Plots.Plot{Plots.PyPlotBackend}:  
ERROR: PyError ($(Expr(:escape, :(ccall(#= /home/yasir/.julia/packages/PyCall/0jMpb/src/pyfncall.jl:44 =# @pysym(:PyObject\_Call), PyPtr, (PyPtr, PyPtr, PyPtr), o, pyargsptr, kw))))) \<class ‘RuntimeError’\>  
RuntimeError('Error in qhull Delaunay triangulation calculation: singular input data (exitcode=2)

---

<div class="post-metadata">

**Author:** ![GantZA](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gantza/32/4867_2.png) [@GantZA](https://discourse.julialang.org/u/GantZA)\
**Post date:** [August 22, 2019, 6:16pm UTC](https://discourse.julialang.org/t/pyerror-runtimeerror-error-in-qhull-delaunay-triangulation-calculation-singular-input/19088/2 "2019-08-22T18:16:29Z")

</div>

I’m getting the same error. Did you eventually fix it?

EDIT: Fixed, I wasn’t using the correct x and y variables