Develop Reference

Map dimensions change when highlighting a country with Geopandas

I create a world map using Geopandas and matplotlib in python. When I try to highlight a certain country, the map dimensions change. How can I preserve the map dimensions?
import matplotlib
from matplotlib import pyplot
from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as FigureCanvas
from matplotlib.collections import PatchCollection
from matplotlib.figure import Figure
import geopandas as gpd
import pandas
self.figure = Figure()
self.canvas = FigureCanvas(self, -1, self.figure)
self.axes = self.figure.add_axes([0, 0, 1, 1])
self.axes.margins(0.0)
self.world_data = gpd.read_file(WORLD)
self.axes.clear()
self.axes.axis('off')
self.figure.set_facecolor(WATER)
self.map_plot = self.world_data.to_crs(epsg=4326).plot(ax=self.axes, color=LAND)
if country_highlight:
self.world_data[self.world_data.ISO_A2_EH ==country_code].plot(edgecolor=u'gray', color='#fa8a48', ax=self.map_plot)
self.canvas.draw()
I attached a runnable below. Each time the user left clicks on the map, a random country is selected. But at each click, map dimensions change. What's wrong here? "ne_110m_admin_0_countries.shp" map file can be downloaded from: this page. You should put the sample code inside the map file directory.
import wx
import matplotlib
from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as FigureCanvas
from matplotlib.figure import Figure
import geopandas as gpd
import random
import pathlib
import os
this_directory = print(pathlib.Path(__file__).parent.resolve())
WORLDX = os.path.join(this_directory, "ne_110m_admin_0_countries.shp")
WATER = '#defafc'
LAND = '#807e7e'
LEFT_MOUSE = matplotlib.backend_bases.MouseButton.LEFT
class MapFrame(wx.Frame):
def __init__(self):
wx.Frame.__init__(self, None, wx.ID_ANY, "Map",
style=wx.DEFAULT_FRAME_STYLE,
size=wx.Size(1200, 900))
self.main_panel = MapPanel(self)
self.Bind(wx.EVT_CLOSE, self.OnClose)
def OnClose(self, _event):
self.Destroy()
wx.Exit()
class MapPanel(wx.Panel):
def __init__(self, parent):
wx.Panel.__init__(self, parent)
self.SetDoubleBuffered(True)
self.figure = Figure()
self.result_frame = parent
self.canvas = FigureCanvas(self, -1, self.figure)
self.axes = self.figure.add_axes([0, 0, 1, 1])
self.axes.margins(0.0)
self.axes.set_anchor('C')
self.sizer = wx.BoxSizer(wx.VERTICAL)
self.sizer.Add(self.canvas, 1, wx.LEFT | wx.TOP | wx.GROW)
self.SetSizer(self.sizer)
self.Fit()
self.Layout()
self.countries = ["US", "FR", "GB", "BR", "IN", "AU", "NZ", "IT", "DE"]
self.gdf = None
self.canvas.mpl_connect('button_press_event', self.onLeftClick)
self.world_data = gpd.read_file(WORLDX)
self.map_plot = None
self.drawMap()
def drawMap(self, country_highlight=None):
"""Draw the map on the canvas. """
self.axes.clear()
self.axes.axis('off')
self.figure.set_facecolor(WATER)
self.map_plot = self.world_data.to_crs(epsg=4326).plot(ax=self.axes, color=LAND)
print("country highlight: ", country_highlight)
if country_highlight:
ylim = self.map_plot.get_ylim()
xlim = self.map_plot.get_xlim()
self.world_data[self.world_data.ISO_A2_EH == country_highlight].plot(edgecolor=u'gray', color='#fa8a48', ax=self.map_plot)
self.map_plot.set_ylim(*ylim)
self.map_plot.set_xlim(*xlim)
self.canvas.draw()
def onLeftClick(self, event):
if event.button == LEFT_MOUSE:
self.drawMap(random.choice(self.countries))
class MyApp(wx.App):
def OnInit(self):
frame = MapFrame()
frame.Show()
return True
if __name__ == "__main__":
app = MyApp()
app.MainLoop()

If you want to hold the map extent for an axis constant after a certain point, you can save them and re-enforce them later:
# I'll drop references to `self` for the rest of the answer for clarity
ax = self.axes
world_data = self.world_data
world_data.to_crs(epsg=4326).plot(ax=ax, color=LAND)
ylim = ax.get_ylim()
xlim = ax.get_xlim()
if country_highlight:
self.world_data[
world_data.ISO_A2_EH == country_code
].plot(edgecolor=u'gray', color='#fa8a48', ax=ax)
ax.set_ylim(*ylim)
ax.set_xlim(*xlim)

Matplotlib canvas won't fit in wxpython panel

I'm trying to show an image inside a panel of a wxpython notebook page using matplotlib. It works perfectly using wx.StaticBitmap but I need to use matplotlib for image manipulation. The code gives this result:
The right panel is a terminal and sizes correctly. The left panel is where the image is meant to fit. The result of wx.lib.inspection is showing that the wxFigureCanvas minsize is (640, 480) but I don't understand why and can't find how to change that. I suspect it's the problem. The code (sorry, short as I could make it):
import cv2 as cv
import matplotlib.pyplot as plt
from matplotlib.figure import Figure
from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as FigureCanvas
import wx
import wx.lib.agw.aui as aui
class TopRight(wx.Panel):
def __init__(self, parent):
super(TopRight, self).__init__(parent)
self.term = wx.TextCtrl(self,
size=(200, 100),
style=wx.TE_MULTILINE|wx.TE_READONLY|wx.TE_RICH
)
self.term.SetDefaultStyle(wx.TextAttr(wx.GREEN))
self.term.SetBackgroundColour(wx.BLACK)
self.sizer = wx.BoxSizer(wx.VERTICAL)
self.sizer.Add(self.term, 1, wx.EXPAND)
self.SetSizer(self.sizer)
self.term.WriteText("hello")
self.term.Update
class TopLeft(wx.Panel):
def __init__(self, parent):
super(TopLeft , self).__init__(parent)
img_pth = "av_cat.png"
# Intitialise the matplotlib figure
self.figure = Figure()
# Create an axes, turn off the labels and add them to the figure
self.axes = plt.Axes(self.figure,[0,0,1,1])
self.axes.set_axis_off()
self.figure.add_axes(self.axes)
# Add the figure to the wxFigureCanvas
self.canvas = FigureCanvas(self, -1, self.figure)
# Sizer to contain the canvas
self.sizer = wx.BoxSizer(wx.VERTICAL)
self.sizer.Add(self.canvas, 1, wx.EXPAND|wx.ALL)
self.SetSizer(self.sizer)
# If there is an initial image, display it on the figure
if img_pth is not None:
self.setImage(img_pth)
def setImage(self, pathToImage):
# Load the image into matplotlib
image = cv.imread(pathToImage)
# Add the image to the figure and redraw the canvas.
self.axes.imshow(image)
self.canvas.draw()
class explorer_panel(wx.Panel):
def __init__(self, parent):
#Constructor
wx.Panel.__init__(self, parent)
topSplitter = wx.SplitterWindow(self)
image_panel = TopLeft(topSplitter)
terminal_panel = TopRight(topSplitter)
topSplitter.SplitVertically(image_panel, terminal_panel)
topSplitter.SetSashGravity(0.5)
sizer = wx.BoxSizer(wx.VERTICAL)
sizer.Add(topSplitter, 1, wx.EXPAND)
self.SetSizer(sizer)
class Main(wx.Frame):
def __init__(self):
wx.Frame.__init__(
self,
parent = None,
title = "Borges Infinite Image",
size = (600,300)
)
panel = wx.Panel(self)
notebook = wx.Notebook(panel)
explorer = explorer_panel(notebook)
notebook.AddPage(explorer, 'Explorer')
sizer = wx.BoxSizer(wx.VERTICAL)
sizer.Add(notebook, 1, wx.ALL|wx.EXPAND, 5)
panel.SetSizer(sizer)
if __name__ == "__main__":
app = wx.App()
frame = Main()
frame.Show()
import wx.lib.inspection as wxli
wxli.InspectionTool().Show()
app.MainLoop()

Update wxpython figure canvas with new figure

In a wxPython application I have an embedded a FigureCanvas with a matplotlib figure. I want to be able to switch the figure by loading a new one. However, the figure is not being updated.
Answers to similar topics suggests that panel.canvas.draw() and panel.Refresh() should do the trick, but I've also tried panel.Update() and panel.canvas.Refresh(). I fear that this only works if you want to redraw the canvas with the same figure?
So my question is: how do you replace the figure inside a canvas and make it update?
Below is a small (non-working) example. First a figure is loaded with a single axis. If you from the embedded shell type panel.LoadFigure() a new figure with 2x2 subplots is created and put into the canvas. But the new figure is not shown.
import numpy as np
import wx
from wx.py.shell import Shell
from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as FigureCanvas
import matplotlib.pyplot as plt
class ShellPanel(wx.Panel):
def __init__(self, parent):
wx.Panel.__init__(self, parent)
self.shell = Shell(self)
self.sizer = wx.BoxSizer(wx.VERTICAL)
self.sizer.Add(self.shell, 1, wx.GROW)
self.SetSizer(self.sizer)
self.Layout()
self.Fit()
class FigurePanel(wx.Panel):
def __init__(self, parent):
wx.Panel.__init__(self, parent)
self.parent = parent
self.sizer = wx.BoxSizer(wx.VERTICAL)
self.figure, ax = plt.subplots()
self.canvas = FigureCanvas(self, -1, self.figure)
self.shellpanel = ShellPanel(self)
s1 = wx.BoxSizer(wx.VERTICAL)
s1.Add(self.canvas, 0, wx.GROW)
s1.Add(self.shellpanel, 1 , wx.EXPAND)
self.sizer.Add(s1, 5, wx.GROW)
self.SetSizer(self.sizer)
self.Layout()
self.Fit()
def LoadFigure(self):
self.figure, ax = plt.subplots(2, 2)
self.canvas.draw()
self.Refresh()
class FigureFrame(wx.Frame):
def __init__(self, parent, id, title, size):
wx.Frame.__init__(self, parent, id, title, size=size)
if __name__ == "__main__":
app = wx.App(False)
fr = FigureFrame(None, -1, title='Figure Loader', size=(wx.DisplaySize()[0]/2, wx.DisplaySize()[1]*3/4))
panel = FigurePanel(fr)
fr.Show()
app.MainLoop()

Is there any reason you are trying to create a new Figure and not simply new Axes on the already defined Figure?
I would write your code like so:
def LoadFigure(self):
self.figure.clf() # clear current figure
# add arbitrary number of new Axes
self.figure.add_subplot(221)
self.figure.add_subplot(222)
self.figure.add_subplot(223)
self.figure.add_subplot(224)
self.canvas.draw() # refresh canvas
EDIT: following your comment, I think the problem is that you're creating a new figure, but your Canvas is still referencing the old one. I don't know if you can change that directly in the FigureCanvas properties, maybe someone with more experience can provide a better answer. For the moment, I would Destroy the previous canvas, and create a new FigureCanvas object with your new figure.
def LoadFigure(self):
self.figure, ax = plt.subplots(2, 2)
self.canvas.Destroy()
self.canvas = FigureCanvas(self, -1, self.figure)
self.canvas.draw()

Try using the Figure itself to make your figure, not pyplot. It has usually worked for me because it gives you more room to improvise.
#!/usr/bin/python
# -*- coding: utf-8 -*-
import numpy as np
import wx
from wx.py.shell import Shell
from matplotlib.figure import Figure
from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as FigureCanvas
import matplotlib.pyplot as plt
class ShellPanel(wx.Panel):
def __init__(self, parent):
wx.Panel.__init__(self, parent)
self.shell = Shell(self)
self.sizer = wx.BoxSizer(wx.VERTICAL)
self.sizer.Add(self.shell, 1, wx.GROW)
self.SetSizer(self.sizer)
self.Layout()
self.Fit()
class FigurePanel(wx.Panel):
def __init__(self, parent):
wx.Panel.__init__(self, parent)
self.parent = parent
self.sizer = wx.BoxSizer(wx.VERTICAL)
self.figure = Figure(figsize = (8,6.1), dpi =60)
self.ax = self.figure.add_subplot(1,1,1)
self.enlarged_figure = Figure(figsize = (8,6.1), dpi = 100)
self.ax2 = self.enlarged_figure.add_subplot(2,1,2)
self.canvas = FigureCanvas(self, -1, self.figure)
self.canvas.Show()
self.enlarged_canvas = FigureCanvas(self,-1,self.enlarged_figure)
self.enlarged_canvas.Show()
self.shellpanel = ShellPanel(self)
s1 = wx.BoxSizer(wx.VERTICAL)
s1.Add(self.canvas, 0, wx.GROW)
s1.Add(self.shellpanel, 1 , wx.EXPAND)
self.sizer.Add(s1, 5, wx.GROW)
self.SetSizer(self.sizer)
self.Layout()
self.Fit()
def LoadFigure(self):
self.figure, ax = plt.subplots(2, 2)
self.canvas.draw()
self.Refresh()
class FigureFrame(wx.Frame):
def __init__(self, parent, id, title, size):
wx.Frame.__init__(self, parent, id, title, size=size)
if __name__ == "__main__":
app = wx.App(False)
fr = FigureFrame(None, -1, title='Figure Loader', size=(wx.DisplaySize()[0]/2, wx.DisplaySize()[1]*3/4))
panel = FigurePanel(fr)
fr.Show()
app.MainLoop()
In the shell type in 'panel.LoadFigure()' and the new figure will show up very quickly and then disappear. Then type 'panel.canvas.draw()' and the new figure will be there. Then type 'panel.LoadFigure()' to load the old figure back. Repeat.
I don't know why the figure remains hidden after the MainLoop() continues but this is sort of a quick fix to your problem.

plotting date series with wxpython and matplotlib - x and y must have same first dimension

I am trying to plot some date series data. As soon as I add the dates I get an error. It works fine if I replace them with numbers. What am I doing wrong?
My code:
import numpy
import matplotlib
matplotlib.use('WXAgg')
from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as FigureCanvas
from matplotlib.backends.backend_wx import NavigationToolbar2Wx
from matplotlib.figure import Figure
import wx
class CanvasPanel(wx.Panel):
def __init__(self, parent):
wx.Panel.__init__(self, parent)
self.figure = Figure()
self.axes = self.figure.add_subplot(111)
self.canvas = FigureCanvas(self, -1, self.figure)
self.sizer = wx.BoxSizer(wx.VERTICAL)
self.sizer.Add(self.canvas, 1, wx.LEFT | wx.TOP | wx.GROW)
self.SetSizer(self.sizer)
self.Fit()
def draw(self):
t = ['1/1/2013','1/2/2013','1/3/2013','1/4/2013','1/5/2013','1/6/2013',
'1/7/2013','1/8/2013','1/9/2013']
s = [100,121,89,111,343,211,151,232,122,343]
self.axes.plot(t, s)
self.tittle1 = wx.StaticText(self, label="My Label")
if __name__ == "__main__":
app = wx.PySimpleApp()
fr = wx.Frame(None, title='My Data')
panel = CanvasPanel(fr)
panel.draw()
fr.Show()
app.MainLoop()
Error:
ValueError: x and y must have same first dimension

In [1]: t = ['1/1/2013','1/2/2013','1/3/2013','1/4/2013','1/5/2013','1/6/2013','1/7/2013','1/8/2013','1/9/2013']
In [2]: s = [100,121,89,111,343,211,151,232,122,343]
In [3]: len(t)
Out[3]: 9
In [4]: len(s)
Out[4]: 10

Matplotlib: Label points on mouseover

I have a scatter plot with several thousand points. This post tells me how to label them:
Matplotlib: How to put individual tags for a scatter plot
But that will look like a disaster with so many points. What I would like instead is to have a "tool tip" type label that pops up when you mouseover a point. Is that possible using matplotlib?

Once you get the coords of the point you can show them or any object-linked info in a textctrl in the toolbar. For this you have to instantiate a toolbar (NavigationToolbar2Wx()) in your canvas and add the textcontrol there. This is not as nice as a popup but it does the job.
Here you have an example of customizing your toolbar (only showing the x coordinate in the txtctrl):
#!/usr/bin/env python
#-*- coding: utf-8 -*-
#
"""
jvisor_spectrum_panel (visor_07)
25 julio 2010
"""
#
import wx
from matplotlib.figure import Figure
from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as FigureCanvas
from matplotlib.backends.backend_wx import NavigationToolbar2Wx
#
#
class SpectrumPanel(wx.Panel):
def __init__(self, parent, xlabel='m/z', ylabel='Intensity'):
wx.Panel.__init__(self, parent)
#
self.parent = parent
self.xlabel = xlabel
self.ylabel = ylabel
self.SetBackgroundColour("white")
#
self.figure = Figure()
self.canvas = FigureCanvas(self, -1, self.figure)
#
self.add_toolbar()
#
sizer = wx.BoxSizer(wx.VERTICAL)
sizer.Add(self.canvas, 1, wx.LEFT | wx.TOP| wx.GROW| wx.EXPAND)
sizer.Add(self.toolbar, 0, wx.LEFT)
self.canvas.mpl_connect('motion_notify_event', self.on_motion)
self.SetSizer(sizer)
self.Fit()
self.clean()
#
def add_toolbar(self):
""
self.toolbar = NavigationToolbar2Wx(self.canvas)
mass_txt = wx.StaticText(self.toolbar, label='m/z', pos=(230, 7),
size=(25, 17))
mass_txt.SetBackgroundColour("light gray")
self.mass = wx.TextCtrl(self.toolbar, pos=(260,4), size=(50, 22),
style=wx.TE_READONLY)
#
self.toolbar.SetToolBitmapSize(wx.Size(24, 25))
self.toolbar.SetMinSize((1500, 31))
self.toolbar.Realize()
self.toolbar.Update()
#
def clean(self):
""
self.figure.clear()
self.axes = self.figure.add_subplot(111)
#
def dibuja(self):
"dibuja el canvas"
self.axes.set_xlabel(self.xlabel)
self.axes.set_ylabel(self.ylabel)
self.canvas.draw()
#
def on_motion(self, evt):
if evt.inaxes:
xpos = evt.xdata
self.mass.SetValue(' %0.1f' % (xpos))
if __name__ == '__main__':
""
class TestFrame(wx.Frame):
def __init__(self, *args, **kargs):
wx.Frame.__init__(self, *args, **kargs)
self.panel = SpectrumPanel(self)
self.Fit()
#
app = wx.PySimpleApp()
fr = TestFrame(None)
fr.Show()
app.MainLoop()
And here you can see the new control in the toolbar: