Reading excel file: ArgumentError: ref of NULL PyObject

[fbanez]

Hi, I am new with Julia. I am trying with ExcelReaders but I get an error.
First, in order to use ExcelReaders I have to do:
ENV["PYTHON"]=""
Pkg.build("PyCall")

It seems to work, but when I try to read some excel file like data = readxl("File.xlsx", "Sheet1!A1:C4"), it gives the error ArgumentError: ref of NULL PyObject

I do not know what is it.
Thank you

[davidanthoff]

Can you post the full code you are trying to run, and the full output you get?

[fbanez]

Sorry! I was out and I forgot to update you. I don't exactly know what I did, but it is working now.
Thnaks!

[ghost]

I met the same problem like him.

using ExcelReaders
data = readxl("/Users/neo/Documents/data.xlsx", "Sheet1!A1:C1572")
#=
LoadError: ArgumentError: ref of NULL PyObject
while loading In[19], in expression starting on line 2

 in getindex at /Users/neo/.julia/v0.4/PyCall/src/PyCall.jl:264
 in readxl at /Users/neo/.julia/v0.4/ExcelReaders/src/ExcelReaders.jl:152
=#

Pkg.installed()
#=
Dict{ASCIIString,VersionNumber} with 48 entries:
  "ExcelReaders"      => v"0.4.1"
  "ZMQ"               => v"0.3.1"
  "ArrayViews"        => v"0.6.4"
  "DataStructures"    => v"0.4.4"
  "Compat"            => v"0.7.18"
  "Calculus"          => v"0.1.14"
  "GZip"              => v"0.2.18"
  "Measures"          => v"0.0.2"
  "StatsFuns"         => v"0.2.2"
  "DataFrames"        => v"0.7.2"
  "Showoff"           => v"0.0.7"
  "Distributions"     => v"0.8.10"
  "FixedPointNumbers" => v"0.1.3"
  "SHA"               => v"0.1.2"
  "DualNumbers"       => v"0.2.2"
  "KernelDensity"     => v"0.1.2"
  "Iterators"         => v"0.1.9"
  "ColorTypes"        => v"0.2.2"
  "Gadfly"            => v"0.4.2"
  "Dates"             => v"0.4.4"
  "Contour"           => v"0.1.0"
  "PDMats"            => v"0.4.1"
  "Optim"             => v"0.4.5"
  "SortingAlgorithms" => v"0.0.6"
  "Conda"             => v"0.2.0"
  ⋮                   => ⋮
=#

My julia version:

➜  ~ julia --version
julia version 0.4.5

Could you please help me? Thank you!

[davidanthoff]

@nixlehrer Could you run Pkg.test("ExcelReaders") and paste the output here? If there is an error with that, could you please try this and report whether it works:

using PyCall
@pyimport math
math.sin(math.pi / 4) - sin(pi / 4)

[ghost]

Thank you for your reply!

julia> Pkg.test("ExcelReaders")
INFO: Testing ExcelReaders
INFO: Recompiling stale cache file /Users/neo/.julia/lib/v0.4/PyCall.ji for module PyCall.
INFO: Recompiling stale cache file /Users/neo/.julia/lib/v0.4/ExcelReaders.ji for module ExcelReaders.
INFO: ExcelReaders tests passed

julia> using PyCall

julia> @pyimport math

julia> math.sin(math.pi / 4) - sin(pi / 4)
0.0

It's now working. It seems because that my sheet was not named by 'Sheet1' before I corrected it.

[davidanthoff]

Ok, thanks!

[shze]

I have hit this problem today on Julia 1.0.2-pre.0 (2018-09-30).

data = openxl("run112+seq+psm.xlsx")
ArgumentError: ref of NULL PyObject

Stacktrace:
 [1] getindex(::PyCall.PyObject, ::String) at /home/sh/.julia/packages/PyCall/0jMpb/src/PyCall.jl:284
 [2] getindex at /home/sh/.julia/packages/PyCall/0jMpb/src/PyCall.jl:294 [inlined]
 [3] openxl(::String) at /home/sh/.julia/packages/ExcelReaders/O29uZ/src/ExcelReaders.jl:64
 [4] top-level scope at In[15]:1

(I'm running this from a Jupyter notebook.)

The sheets in this Excel file have long names with spaces; changing them the SheetN does not help.

Trying to loading a specific sheet results in the same error:
data = readxlsheet("run112+seq+psm.xlsx", "Protein View")

It seems that ExcelReaders is installed correctly:

Pkg.test("ExcelReaders")
   Testing ExcelReaders
    Status `/tmp/tmpQBK8Si/Manifest.toml`
  [34da2185] Compat v1.3.0
  [8f4d0f93] Conda v1.1.1
  ... <omitted 28 lines>
  [cf7118a7] UUIDs  [`@stdlib/UUIDs`]
  [4ec0a83e] Unicode  [`@stdlib/Unicode`]
Test Summary: | Pass  Total
ExcelReaders  |  245    245
   Testing ExcelReaders tests passed 

Any idea how to get this to run? Anything else I could try?

Thanks!

[davidanthoff]

Hm, any chance you could share the original file? If you can't share it publicly, maybe you could email me a copy?

[shze]

I'll email you the file.

[shze]

Were you able to find anything?