# Control the behaviour of PyCall

**URL:** https://discourse.julialang.org/t/control-the-behaviour-of-pycall/10182
**Category:** New to Julia
**Tags:** pycall
**Created:** [April 5, 2018, 4:13pm UTC](https://discourse.julialang.org/t/control-the-behaviour-of-pycall/10182 "2018-04-05T16:13:11Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![Balinus](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/balinus/32/243_2.png) [@Balinus](https://discourse.julialang.org/u/Balinus)
#### Post date: [April 5, 2018, 4:13pm UTC](https://discourse.julialang.org/t/control-the-behaviour-of-pycall/10182/1 "2018-04-05T16:13:11Z")

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Hello,

not sure it’s the right place to ask the question, I’ll be happy to ask elsewhere if it’s the case.

The following code is based on this [blog post on Medium](https://medium.com/@plotlygraphs/how-to-create-2d-and-3d-interactive-weather-maps-in-python-and-r-77ddd53cca8).

I’m calling basemap through PyCall and when I execute the following code I get the right results, but it triggers a figure. I was wondering how to prevent the figure from appearing. The figure appears when the line `poly_paths = m[:drawcoastlines]()[:get_paths]()` is executed.

Thanks for any help!

**MWE**

```julia
using PlotlyJS
using PyPlot
using PyCall

const basemap = PyNULL()
copy!(basemap, pyimport_conda("mpl_toolkits.basemap", "basemap"))

m = basemap[:Basemap]()

function polygons_to_traces(poly_paths, N_poly)
    """
    pos arg 1. (poly_paths): paths to polygons
    pos arg 2. (N_poly): number of polygon to convert
    """
    # init. plotting list
    data = Dict(
        "x" => [],
        "y" => [],
        "mode" => "lines",
        "line" => line(color="black"),
        "name" => ""
    )

    for i_poly in 1:N_poly
        poly_path = poly_paths[i_poly]

        # get the Basemap coordinates of each segment
        coords_cc = [vertex for vertex in poly_path[:vertices]]

        # convert coordinates to lon/lat by 'inverting' the Basemap projection
        lon_cc, lat_cc = m(coords_cc[:,1],coords_cc[:,2], inverse=true)

        # add plot.ly plotting options
        append!(data["x"], [lon_cc; NaN])
        # push!(data["x"], NaN)
        append!(data["y"], [lat_cc; NaN])
        # push!(data["y"], NaN)
    end     

    return data
end

function get_coastline_traces()
    poly_paths = m[:drawcoastlines]()[:get_paths](); # coastline polygon paths
    N_poly = 91

    return polygons_to_traces(poly_paths, N_poly)
end

coastlines = get_coastline_traces()

```

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<div class="post-metadata">

### Author: ![Balinus](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/balinus/32/243_2.png) [@Balinus](https://discourse.julialang.org/u/Balinus)
#### Post date: [April 5, 2018, 4:23pm UTC](https://discourse.julialang.org/t/control-the-behaviour-of-pycall/10182/2 "2018-04-05T16:23:43Z")

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Nevermind! Found a solution. I added the following in the preambule

```julia
const plt = PyNULL()
copy!(plt, pyimport_conda("matplotlib.pyplot", "matplotlib"))

```

add redefined the function as follow

```julia
function get_coastline_traces()
    plt[:ioff]()
    poly_paths = m[:drawcoastlines]()[:get_paths](); # coastline polygon paths
    plt[:ion]()
    N_poly = 91

    return polygons_to_traces(poly_paths, N_poly)
end

```

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### Author: ![cstjean](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/cstjean/32/1444_2.png) [@cstjean](https://discourse.julialang.org/u/cstjean)
#### Post date: [April 6, 2018, 1:05am UTC](https://discourse.julialang.org/t/control-the-behaviour-of-pycall/10182/3 "2018-04-06T01:05:25Z")

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> [@Balinus](#):
>
> copy!(plt, pyimport\_conda(“matplotlib.pyplot”, “matplotlib”))

I might be wrong, but IIRC you should put this line in your ` __init__ ` function, otherwise precompilation won’t work. If you don’t care about precompilation, you could just write `const basemap = pyimport(...)`.

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### Author: ![Balinus](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/balinus/32/243_2.png) [@Balinus](https://discourse.julialang.org/u/Balinus)
#### Post date: [April 6, 2018, 12:59pm UTC](https://discourse.julialang.org/t/control-the-behaviour-of-pycall/10182/4 "2018-04-06T12:59:30Z")

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Salut,

I should have mentioned that the line is indeed inside the **init** function of the module file definition (i.e. [ClimateTools.jl](https://github.com/Balinus/ClimateTools.jl/blob/master/src/ClimateTools.jl), not updated yet).

Thanks for the clarification though, the solution is more complete with it. 🙂