PythonPlot.streamplot error

Wen-Wei_Tseng
Tue, 24 Mar 2026 15:28:28 +0000
Visualization

Hello, I was trying to generate a stream plot using PythonPlot.jl like this example: Julia_Examples/pyplot_streamplot.jl at master · gizmaa/Julia_Examples · GitHub

However, I was encounter an error while running the following code. I would like to know how to correctly call streamplot() under PythonPlot.jl .

using PythonPlot

## This works
x = range(0; stop=2*pi, length=1000)
y = sin.(3 * x + 4 * cos.(2 * x))
plot(x, y, color="red", linewidth=2.0, linestyle="--")
title("A sinusoidally modulated sinusoid")
gcf()

#---
minval = -3
maxval = 3
steps = 100
X = repeat(range(minval,stop=maxval,length=steps)',steps)
Y = repeat(range(minval,stop=maxval,length=steps),1,steps)
U = -1 .- X.^2 .+ Y
V = 1 .+ X .- Y.^2
speed = sqrt.(U.^2 .+ V.^2)

fig = figure("pyplot_streamplot",figsize=(10,10))
subplot(311)
streamplot(X,Y,U,V) ## This line gives error

Error message:

ERROR: Python: Julia: an error occurred while setting an error
Python stacktrace:
 [1] __getitem__
   @ C:\Users\sosiristseng\.julia\packages\PythonCall\83z4q\src\JlWrap\array.jl:350
 [2] __init__
   @ matplotlib.streamplot d:\github\mmsb-bebi-5009\.CondaPkg\.pixi\envs\default\Lib\site-packages\matplotlib\streamplot.py:329
 [3] streamplot
   @ matplotlib.streamplot d:\github\mmsb-bebi-5009\.CondaPkg\.pixi\envs\default\Lib\site-packages\matplotlib\streamplot.py:91
 [4] inner
   @ matplotlib d:\github\mmsb-bebi-5009\.CondaPkg\.pixi\envs\default\Lib\site-packages\matplotlib\__init__.py:1524
 [5] streamplot
   @ matplotlib.pyplot d:\github\mmsb-bebi-5009\.CondaPkg\.pixi\envs\default\Lib\site-packages\matplotlib\pyplot.py:4141
Stacktrace:
 [1] pythrow()
   @ PythonCall.Core C:\Users\sosiristseng\.julia\packages\PythonCall\83z4q\src\Core\err.jl:77
 [2] errcheck
   @ C:\Users\sosiristseng\.julia\packages\PythonCall\83z4q\src\Core\err.jl:10 [inlined]
 [3] pycallargs(f::PythonCall.Py, args::PythonCall.Py)
   @ PythonCall.Core C:\Users\sosiristseng\.julia\packages\PythonCall\83z4q\src\Core\builtins.jl:194
 [4] pycall(::PythonCall.Py, ::Matrix{Float64}, ::Vararg{Matrix{Float64}}; kwargs::@Kwargs{})
   @ PythonCall.Core C:\Users\sosiristseng\.julia\packages\PythonCall\83z4q\src\Core\builtins.jl:213
 [5] pycall(::PythonCall.Py, ::Matrix{Float64}, ::Vararg{Matrix{Float64}})
   @ PythonCall.Core C:\Users\sosiristseng\.julia\packages\PythonCall\83z4q\src\Core\builtins.jl:203
 [6] streamplot(::Matrix{Float64}, ::Vararg{Matrix{Float64}}; kws::@Kwargs{})
   @ PythonPlot C:\Users\sosiristseng\.julia\packages\PythonPlot\oS8x4\src\PythonPlot.jl:179
 [7] streamplot(::Matrix{Float64}, ::Vararg{Matrix{Float64}})
   @ PythonPlot C:\Users\sosiristseng\.julia\packages\PythonPlot\oS8x4\src\PythonPlot.jl:175
 [8] top-level scope
   @ d:\github\mmsb-bebi-5009\test.jl:22

System info

Julia Version 1.12.5
OS: Windows 11 24H2

Installed packages

  [274fc56d] + PythonPlot v1.0.6

Manifest

  [3da002f7] + ColorTypes v0.12.1
  [5ae59095] + Colors v0.13.1
  [992eb4ea] + CondaPkg v0.2.34
  [9a962f9c] + DataAPI v1.16.0
  [e2d170a0] + DataValueInterfaces v1.0.0
  [53c48c17] + FixedPointNumbers v0.8.5
  [82899510] + IteratorInterfaceExtensions v1.0.0
  [692b3bcd] + JLLWrappers v1.7.1
  [682c06a0] + JSON v1.4.0
  [b964fa9f] + LaTeXStrings v1.4.0
  [1914dd2f] + MacroTools v0.5.16
  [0b3b1443] + MicroMamba v0.1.15
  [bac558e1] + OrderedCollections v1.8.1
  [69de0a69] + Parsers v2.8.3
  [fa939f87] + Pidfile v1.3.0
  [aea7be01] + PrecompileTools v1.3.3
  [21216c6a] + Preferences v1.5.2
  [6099a3de] + PythonCall v0.9.31
  [274fc56d] + PythonPlot v1.0.6
  [189a3867] + Reexport v1.2.2
  [6c6a2e73] + Scratch v1.3.0
  [10745b16] + Statistics v1.11.1
  [ec057cc2] + StructUtils v2.7.1
  [3783bdb8] + TableTraits v1.0.1
  [bd369af6] + Tables v1.12.1
  [e17b2a0c] + UnsafePointers v1.0.0
  [81def892] + VersionParsing v1.3.0
  [f8abcde7] + micromamba_jll v2.3.1+0
  [4d7b5844] + pixi_jll v0.41.3+0
  [0dad84c5] + ArgTools v1.1.2
  [56f22d72] + Artifacts v1.11.0
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  [ca575930] + NetworkOptions v1.3.0
  [44cfe95a] + Pkg v1.12.1
  [de0858da] + Printf v1.11.0
  [9a3f8284] + Random v1.11.0
  [ea8e919c] + SHA v0.7.0
  [9e88b42a] + Serialization v1.11.0
  [6462fe0b] + Sockets v1.11.0
  [f489334b] + StyledStrings v1.11.0
  [fa267f1f] + TOML v1.0.3
  [a4e569a6] + Tar v1.10.0
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  [4ec0a83e] + Unicode v1.11.0
  [e66e0078] + CompilerSupportLibraries_jll v1.3.0+1
  [deac9b47] + LibCURL_jll v8.15.0+0
  [e37daf67] + LibGit2_jll v1.9.0+0
  [29816b5a] + LibSSH2_jll v1.11.3+1
  [14a3606d] + MozillaCACerts_jll v2025.11.4
  [4536629a] + OpenBLAS_jll v0.3.29+0
  [458c3c95] + OpenSSL_jll v3.5.4+0
  [83775a58] + Zlib_jll v1.3.1+2
  [8e850b90] + libblastrampoline_jll v5.15.0+0
  [8e850ede] + nghttp2_jll v1.64.0+1
  [3f19e933] + p7zip_jll v17.7.0+0

3 posts - 2 participants