OS X - How to create QLabel which just fits its text with exotic character? - qt

In the following code, characterLabel is small a bit.
But characterLabelEntire is too big.
How to create QLabel which just fits its text?
from PySide.QtCore import *
from PySide.QtGui import *
targetChar = unichr(0x0e0e)
# Setting
font = QFont()
font.setPointSize(50)
sizePolicy = QSizePolicy(QSizePolicy.Maximum, QSizePolicy.Maximum)
# Following code will create a character label.
# But it seems the size of the label is small a bit.
# Becasue some of the region of the character is lost.
characterLabel = QLabel(targetChar)
characterLabel.setFont(font)
characterLabel.setSizePolicy(sizePolicy)
# Following code will create a character label, but it's too big.
characterLabelEntire = QLabel(targetChar)
characterLabelEntire.setFont(font)
characterLabelEntire.setFixedSize(100, 100)
characterLabel.setSizePolicy(sizePolicy)
# Show and Raise
characterLabel.show()
characterLabelEntire.show()
characterLabel.raise_()
characterLabelEntire.raise_()
try:
app = QApplication([])
app.exec_()
except:
pass
It seems Exotic character designer break font rule?
I found the following article.
http://doc.qt.io/qt-4.8/qfontmetrics.html#descent
Anyway, in my environment(OS X 10.11), larger descent is needed to show the entire character image.
from PySide.QtCore import *
from PySide.QtGui import *
try:
app = QApplication([])
except:
pass
targetChar = unichr(0x0e0e)
# Setting
font = QFont()
font.setPointSize(100)
# Following code will create a character label.
characterLabel = QLabel(targetChar)
characterLabel.setFont(font)
fm = characterLabel.fontMetrics()
pixelsWide = fm.width(targetChar)
pixelsHigh = fm.ascent() + fm.descent() * 3
characterLabel.setFixedSize(pixelsWide, pixelsHigh)
characterLabel.show()
characterLabel.raise_()
try:
app.exec_()
except:
pass

Related

bokeh selected.on_change not working for my current setup

Basically, this is an interactive heatmap but the twist is that the source is updated by reading values from a file that gets updated regularly.
dont bother about the class "generator", it is just for keeping data and it runs regularly threaded
make sure a file named "Server_dump.txt" exists in the same directory of the script with a single number greater than 0 inside before u execute the bokeh script.
what basically happens is i change a number inside the file named "Server_dump.txt" by using echo 4 > Server_dump.txt on bash,
u can put any number other than 4 and the script automatically checks the file and plots the new point.
if u don't use bash, u could use a text editor , replace the number and save, and all will be the same.
the run function inside the generator class is the one which checks if this file was modified , reads the number, transforms it into x& y coords and increments the number of taps associated with these coords and gives the source x,y,taps values based on that number.
well that function works fine and each time i echo a number , the correct rectangle is plotted but,
now I want to add the functionality of that clicking on a certain rectangle triggers a callback to plot a second graph based on the coords of the clicked rectangle but i can't even get it to trigger even though i have tried other examples with selected.on_change in them and they worked fine.
*if i increase self.taps for a certain rect by writing the number to the file multiple times, color gets updated but if i hover over the rect it shows me the past values and not the latest value only .
my bokeh version is 1.0.4
from functools import partial
from random import random,randint
import threading
import time
from tornado import gen
from os.path import getmtime
from math import pi
import pandas as pd
from random import randint, random
from bokeh.io import show
from bokeh.models import LinearColorMapper, BasicTicker, widgets, PrintfTickFormatter, ColorBar, ColumnDataSource, FactorRange
from bokeh.plotting import figure, curdoc
from bokeh.layouts import row, column, gridplot
source = ColumnDataSource(data=dict(x=[], y=[], taps=[]))
doc = curdoc()
#sloppy data receiving function to change data to a plottable shape
class generator(threading.Thread):
def __init__(self):
super(generator, self).__init__()
self.chart_coords = {'x':[],'y':[],'taps':[]}
self.Pi_coords = {}
self.coord = 0
self.pos = 0
self.col = 0
self.row = 0
self.s = 0
self.t = 0
def chart_dict_gen(self,row, col):
self.col = col
self.row = row+1
self.chart_coords['x'] = [i for i in range(1,cla.row)]
self.chart_coords['y'] = [i for i in range(cla.col, 0, -1)] #reversed list because chart requires that
self.chart_coords['taps']= [0]*(row * col)
self.taps = [[0 for y in range(col)] for x in range(row)]
def Pi_dict_gen(self,row,col):
key = 1
for x in range(1,row):
for y in range(1,col):
self.Pi_coords[key] = (x,y)
key = key + 1
def Pi_to_chart(self,N):
x,y = self.Pi_coords[N][0], self.Pi_coords[N][1]
return x,y
def run(self):
while True:
if(self.t == 0):
self.t=1
continue
time.sleep(0.1)
h = getmtime("Server_dump.txt")
if self.s != h:
self.s = h
with open('Server_dump.txt') as f:
m = next(f)
y,x = self.Pi_to_chart(int(m))
self.taps[x][y] += 1
# but update the document from callback
doc.add_next_tick_callback(partial(update, x=x, y=y, taps=self.taps[x][y]))
cla = generator()
cla.chart_dict_gen(15,15)
cla.Pi_dict_gen(15, 15)
x = cla.chart_coords['x']
y = cla.chart_coords['y']
taps = cla.chart_coords['taps']
#gen.coroutine
def update(x, y, taps):
taps += taps
print(x,y,taps)
source.stream(dict(x=[x], y=[y], taps=[taps]))
colors = ["#CCEBFF","#B2E0FF","#99D6FF","#80CCFF","#66c2FF","#4DB8FF","#33ADFF","#19A3FF", "#0099FF", "#008AE6", "#007ACC","#006BB2", "#005C99", "#004C80", "#003D66", "#002E4C", "#001F33", "#000F1A", "#000000"]
mapper = LinearColorMapper(palette=colors, low= 0, high= 15) #low = min(cla.chart_coords['taps']) high = max(cla.chart_coords['taps'])
TOOLS = "hover,save,pan,box_zoom,reset,wheel_zoom"
p = figure(title="Tou",
x_range=list(map(str,x)),
y_range=list(map(str,reversed(y))),
x_axis_location="above",
plot_width=900, plot_height=400,
tools=TOOLS, toolbar_location='below',
tooltips=[('coords', '#y #x'), ('taps', '#taps%')])
p.grid.grid_line_color = "#ffffff"
p.axis.axis_line_color = "#ef4723"
p.axis.major_tick_line_color = "#af0a36"
p.axis.major_label_text_font_size = "7pt"
p.xgrid.grid_line_color = None
p.ygrid.grid_line_color = None
p.rect(x="x", y="y",
width=0.9, height=0.9,
source=source,
fill_color={'field': 'taps', 'transform': mapper},
line_color = "#ffffff",
)
color_bar = ColorBar(color_mapper=mapper,
major_label_text_font_size="7pt",
ticker=BasicTicker(desired_num_ticks=len(colors)),
formatter=PrintfTickFormatter(format="%d%%"),
label_standoff=6, border_line_color=None, location=(0, 0))
curdoc().theme = 'dark_minimal'
def ck(attr, old, new):
print('here') #doesn't even print hi in the terminal if i click anywhere
source.selected.on_change('indices', ck)
p.add_layout(color_bar, 'right')
doc.add_root(p)
thread = cla
thread.start()
i wanted even to get a printed hi in the terminal but nothing
You have not actually added any selection tool at all to your plot, so no selection is ever made. You have specified:
TOOLS = "hover,save,pan,box_zoom,reset,wheel_zoom"
Those are the only tools that will be added, and none of them make selections, there for nothing will cause source.selection.indices to ever be updated. If you are looking for selections based on tap, you must add a TapTool, e.g. with
TOOLS = "hover,save,pan,box_zoom,reset,wheel_zoom,tap"
Note that there will not be repeated callbacks if you tap the same rect multiple times. The callback only fires when the selection changes and clicking the same glyph twice in a row results in an identical selection.

ipywidgets: Automatically update variable and run code after altering widget value

I have been trying to automatically update a variable and run a code snippet after altering a ipywidget.
So far the only partial solution I have found is to declare a global variable kind of following the example on the github (here):
import ipywidgets as widgets
from IPython.display import display
x = 5
slider = widgets.IntSlider()
slider.value = x
def on_change(v):
global x
x = v['new']
slider.observe(on_change, names='value')
display(slider)
Ideally what I am trying to achieve is to automatically change the x value after altering the widget without the use of global variables and also change some previously defined variables. It would be something like this:
x = 5
y = []
slider = widgets.IntSlider()
slider.value = x
def on_change(v):
x = v['new']
y.append(x)
slider.observe(on_change, names='value')
display(slider)
One way to achieve this would to be to make a class that accepts the new widget value, and does the derived calculation as well. I've done a simple addition but you could append to a list.
import ipywidgets as widgets
class Updated:
def __init__(self):
self.widget_value = None
self.derived_value = None
def update(self, val_dict) -> None:
self.widget_value = val_dict['new']
self.derived_value = self.widget_value + 10
update_class = Updated()
x = 5
y = []
slider = widgets.IntSlider()
slider.value = x
def on_change(v):
update_class.update(v)
slider.observe(on_change, names='value')
display(slider)
You can then see how update_class.widget_value and update_class.derived_value change as you move the slider.

Bokeh Colorbar Vertical title to right of colorbar?

I'm trying to do something that I'd normally consider trivial but seems to be very difficult in bokeh: Adding a vertical colorbar to a plot and then having the title of the colorbar (a.k.a. the variable behind the colormapping) appear to one side of the colorbar but rotated 90 degrees clockwise from horizontal.
From what I can tell of the bokeh ColorBar() interface (looking at both documentation and using the python interpreter's help() function for this element), this is not possible. In desperation I have added my own Label()-based annotation. This works but is klunky and displays odd behavior when deployed in a bokeh serve situation--that the width of the data window on the plot varies inversely with the length of the title colorbar's title string.
Below I've included a modified version of the bokeh server mpg example. Apologies for its complexity, but I felt this was the best way to illustrate the problem using infrastructure/data that ships with bokeh. For those unfamiliar with bokeh serve, this code snippet needs to saved to a file named main.py that resides in a directory--for the sake of argument let's say CrossFilter2--and in the parent directory of CrossFilter2 one needs to invoke the command
bokeh serve --show CrossFilter2
this will then display in a browser window (localhost:5006/CrossFilter2) and if you play with the color selection widget you will see what I mean, namely that short variable names such as 'hp' or 'mpg' result in a wider data display windows than longer variable names such as 'accel' or 'weight'. I suspect that there may be a bug in how label elements are sized--that their x and y dimensions are swapped--and that bokeh has not understood that the label element has been rotated.
My questions are:
Must I really have to go to this kind of trouble to get a simple colorbar label feature that I can get with little-to-no trouble in matplotlib/plotly?
If I must go through the hassle you can see in my sample code, is there some other way I can do this that avoids the data window width problem?
import numpy as np
import pandas as pd
from bokeh.layouts import row, widgetbox
from bokeh.models import Select
from bokeh.models import HoverTool, ColorBar, LinearColorMapper, Label
from bokeh.palettes import Spectral5
from bokeh.plotting import curdoc, figure, ColumnDataSource
from bokeh.sampledata.autompg import autompg_clean as df
df = df.copy()
SIZES = list(range(6, 22, 3))
COLORS = Spectral5
# data cleanup
df.cyl = df.cyl.astype(str)
df.yr = df.yr.astype(str)
columns = sorted(df.columns)
discrete = [x for x in columns if df[x].dtype == object]
continuous = [x for x in columns if x not in discrete]
quantileable = [x for x in continuous if len(df[x].unique()) > 20]
def create_figure():
xs = df[x.value].tolist()
ys = df[y.value].tolist()
x_title = x.value.title()
y_title = y.value.title()
name = df['name'].tolist()
kw = dict()
if x.value in discrete:
kw['x_range'] = sorted(set(xs))
if y.value in discrete:
kw['y_range'] = sorted(set(ys))
kw['title'] = "%s vs %s" % (y_title, x_title)
p = figure(plot_height=600, plot_width=800,
tools='pan,box_zoom,wheel_zoom,lasso_select,reset,save',
toolbar_location='above', **kw)
p.xaxis.axis_label = x_title
p.yaxis.axis_label = y_title
if x.value in discrete:
p.xaxis.major_label_orientation = pd.np.pi / 4
if size.value != 'None':
groups = pd.qcut(df[size.value].values, len(SIZES))
sz = [SIZES[xx] for xx in groups.codes]
else:
sz = [9] * len(xs)
if color.value != 'None':
coloring = df[color.value].tolist()
cv_95 = np.percentile(np.asarray(coloring), 95)
mapper = LinearColorMapper(palette=Spectral5,
low=cv_min, high=cv_95)
mapper.low_color = 'blue'
mapper.high_color = 'red'
add_color_bar = True
ninety_degrees = pd.np.pi / 2.
color_bar = ColorBar(color_mapper=mapper, title='',
#title=color.value.title(),
title_text_font_style='bold',
title_text_font_size='20px',
title_text_align='center',
orientation='vertical',
major_label_text_font_size='16px',
major_label_text_font_style='bold',
label_standoff=8,
major_tick_line_color='black',
major_tick_line_width=3,
major_tick_in=12,
location=(0,0))
else:
c = ['#31AADE'] * len(xs)
add_color_bar = False
if add_color_bar:
source = ColumnDataSource(data=dict(x=xs, y=ys,
c=coloring, size=sz, name=name))
else:
source = ColumnDataSource(data=dict(x=xs, y=ys, color=c,
size=sz, name=name))
if add_color_bar:
p.circle('x', 'y', fill_color={'field': 'c',
'transform': mapper},
line_color=None, size='size', source=source)
else:
p.circle('x', 'y', color='color', size='size', source=source)
p.add_tools(HoverTool(tooltips=[('x', '#x'), ('y', '#y'),
('desc', '#name')]))
if add_color_bar:
color_bar_label = Label(text=color.value.title(),
angle=ninety_degrees,
text_color='black',
text_font_style='bold',
text_font_size='20px',
x=25, y=300,
x_units='screen', y_units='screen')
p.add_layout(color_bar, 'right')
p.add_layout(color_bar_label, 'right')
return p
def update(attr, old, new):
layout.children[1] = create_figure()
x = Select(title='X-Axis', value='mpg', options=columns)
x.on_change('value', update)
y = Select(title='Y-Axis', value='hp', options=columns)
y.on_change('value', update)
size = Select(title='Size', value='None',
options=['None'] + quantileable)
size.on_change('value', update)
color = Select(title='Color', value='None',
options=['None'] + quantileable)
color.on_change('value', update)
controls = widgetbox([x, y, color, size], width=200)
layout = row(controls, create_figure())
curdoc().add_root(layout)
curdoc().title = "Crossfilter"
You can add a vertical label to the Colorbar by plotting it on a separate axis and adding a title to this axis. To illustrate this, here's a modified version of Bokeh's standard Colorbar example (found here):
import numpy as np
from bokeh.plotting import figure, output_file, show
from bokeh.models import LogColorMapper, LogTicker, ColorBar
from bokeh.layouts import row
plot_height = 500
plot_width = 500
color_bar_height = plot_height + 11
color_bar_width = 180
output_file('color_bar.html')
def normal2d(X, Y, sigx=1.0, sigy=1.0, mux=0.0, muy=0.0):
z = (X-mux)**2 / sigx**2 + (Y-muy)**2 / sigy**2
return np.exp(-z/2) / (2 * np.pi * sigx * sigy)
X, Y = np.mgrid[-3:3:100j, -2:2:100j]
Z = normal2d(X, Y, 0.1, 0.2, 1.0, 1.0) + 0.1*normal2d(X, Y, 1.0, 1.0)
image = Z * 1e6
color_mapper = LogColorMapper(palette="Viridis256", low=1, high=1e7)
plot = figure(x_range=(0,1), y_range=(0,1), toolbar_location=None,
width=plot_width, height=plot_height)
plot.image(image=[image], color_mapper=color_mapper,
dh=[1.0], dw=[1.0], x=[0], y=[0])
Now, to make the Colorbar, create a separate dummy plot, add the Colorbar to the dummy plot and place it next to the main plot. Add the Colorbar label as the title of the dummy plot and center it appropriately.
color_bar = ColorBar(color_mapper=color_mapper, ticker=LogTicker(),
label_standoff=12, border_line_color=None, location=(0,0))
color_bar_plot = figure(title="My color bar title", title_location="right",
height=color_bar_height, width=color_bar_width,
toolbar_location=None, min_border=0,
outline_line_color=None)
color_bar_plot.add_layout(color_bar, 'right')
color_bar_plot.title.align="center"
color_bar_plot.title.text_font_size = '12pt'
layout = row(plot, color_bar_plot)
show(layout)
This gives the following output image:
One thing to look out for is that color_bar_width is set wide enough to incorporate both the Colorbar, its axes labels and the Colorbar label. If the width is set too small, you will get an error and the plot won't render.
As of Bokeh 0.12.10 there is no built in label available for colorbars. In addition to your approach or something like it, another possibility would be a custom extension, though that is similarly not trivial.
Offhand, a colobar label certainly seems like a reasonable thing to consider. Regarding the notion that it ought to be trivially available, if you polled all users about what they consider should be trivially available, there will be thousands of different suggestions for what to prioritize. As is very often the case in the OSS world, there are far more possible things to do, than there are people to do them (less than 3 in this case). So, would first suggest a GitHub Issue to request the feature, and second, if you have the ability, volunteering to help implement it. Your contribution would be valuable and appreciated by many.

ImageView.setImage axes parameter does not switch X-Y dimensions

I have modified the ImageView example by adding the statement data[:, ::10, :] = 0, which sets every tenth element of the middle dimension to 0. The program now shows horizontal lines. This is consistent with the documentation of the ImageView.setImage function: the default axes dictionary is {'t':0, 'x':1, 'y':2, 'c':3}. However, when I change this to {'t':0, 'x':2, 'y':1, 'c':3}, nothing changes where I would expect to get vertical rows.
So my question is: how can I give the row dimension a higher precedence in PyQtGraph? Of course I can transpose all my arrays myself before passing them to the setImage function but I prefer not to. Especially since both Numpy and Qt use the row/column convention and not X before Y. I don't see why PyQtGraph chooses the latter.
For completeness, find my modified ImageView example below.
import numpy as np
from pyqtgraph.Qt import QtCore, QtGui
import pyqtgraph as pg
app = QtGui.QApplication([])
## Create window with ImageView widget
win = QtGui.QMainWindow()
win.resize(800,800)
imv = pg.ImageView()
win.setCentralWidget(imv)
win.show()
win.setWindowTitle('pyqtgraph example: ImageView')
## Create random 3D data set with noisy signals
img = pg.gaussianFilter(np.random.normal(size=(200, 200)), (5, 5)) * 20 + 100
img = img[np.newaxis,:,:]
decay = np.exp(-np.linspace(0,0.3,100))[:,np.newaxis,np.newaxis]
data = np.random.normal(size=(100, 200, 200))
data += img * decay
data += 2
## Add time-varying signal
sig = np.zeros(data.shape[0])
sig[30:] += np.exp(-np.linspace(1,10, 70))
sig[40:] += np.exp(-np.linspace(1,10, 60))
sig[70:] += np.exp(-np.linspace(1,10, 30))
sig = sig[:,np.newaxis,np.newaxis] * 3
data[:,50:60,50:60] += sig
data[:, ::10, :] = 0 # Make image a-symmetrical
## Display the data and assign each frame a time value from 1.0 to 3.0
imv.setImage(data, xvals=np.linspace(1., 3., data.shape[0]),
axes={'t':0, 'x':2, 'y':1, 'c':3}) # doesn't help
## Start Qt event loop unless running in interactive mode.
if __name__ == '__main__':
import sys
if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
QtGui.QApplication.instance().exec_()
Looking through ImageView.py, setImage() parses the axes dictionary and based on presence of 't' it builds the z-axis/frame slider, and that's it. Rearranging the axes seems unimplemented yet.

Python3: How to dynamically resize button text in tkinter/ttk?

I want to know how to arrange for the text on a ttk widget (a label or button, say) to resize automatically.
Changing the size of the text is easy, it is just a matter of changing the font in the style. However, hooking it into changes in the size of the window is a little more tricky. Looking on the web I found some hints, but there was nowhere a complete answer was posted.
So, here below is a complete working example posted as an answer to my own question. I hope someone finds it useful. If anyone has further improvements to suggest, I will be delighted to see them!
The example below shows two techniques, one activated by re-sizing the window (see the resize() method, bound to the <Configure> event), and the other by directly changing the size of the font (see the mutate() method).
Other code necessary to get resizing working is the grid configuration code in the __init__() method.
When running the example, there is some interaction between the two methods, but I think in a 'real' situation one technique would be sufficient, so that issue won't arise.
from tkinter import *
from tkinter.ttk import *
class ButtonApp(Frame):
"""Container for the buttons."""
def __init__(self, master=None):
"""Initialize the frame and its children."""
super().__init__(master)
self.createWidgets()
# configure the frame's resize behaviour
master.columnconfigure(0, weight=1)
master.rowconfigure(0, weight=1)
self.grid(sticky=(N,S,E,W))
# configure resize behaviour for the frame's children
self.columnconfigure(0, weight=1)
self.rowconfigure(0, weight=1)
self.rowconfigure(0, weight=1)
# bind to window resize events
self.bind('<Configure>', self.resize)
def createWidgets(self):
"""Make the widgets."""
# this button mutates
self.mutantButton = Button(self, text='Press Me',
style='10.TButton')
self.mutantButton.grid(column=0, row=0, sticky=(N,S,E,W))
self.mutantButton['command'] = self.mutate
# an ordinary quit button for comparison
self.quitButton = Button(self, text='Quit', style='TButton')
self.quitButton.grid(column=0, row=1, sticky=(N,S,E,W))
self.quitButton['command'] = self.quit
def mutate(self):
"""Rotate through the styles by hitting the button."""
style = int(self.mutantButton['style'].split('.')[0])
newStyle = style + 5
if newStyle > 50: newStyle = 10
print('Choosing font '+str(newStyle))
self.mutantButton['style'] = fontStyle[newStyle]
# resize the frame
# get the current geometries
currentGeometry = self._root().geometry()
w, h, x, y = self.parseGeometry(currentGeometry)
reqWidth = self.mutantButton.winfo_reqwidth()
reqHeight = self.mutantButton.winfo_reqheight()
# note assume height of quit button is constant at 20.
w = max([w, reqWidth])
h = 20 + reqHeight
self._root().geometry('%dx%d+%d+%d' % (w, h, x, y))
def parseGeometry(self, geometry):
"""Geometry parser.
Returns the geometry as a (w, h, x, y) tuple."""
# get w
xsplit = geometry.split('x')
w = int(xsplit[0])
rest = xsplit[1]
# get h, x, y
plussplit = rest.split('+')
h = int(plussplit[0])
x = int(plussplit[1])
y = int(plussplit[2])
return w, h, x, y
def resize(self, event):
"""Method bound to the <Configure> event for resizing."""
# get geometry info from the root window.
wm, hm = self._root().winfo_width(), self._root().winfo_height()
# choose a font height to match
# note subtract 30 for the button we are NOT scaling.
# note we assume optimal font height is 1/2 widget height.
fontHeight = (hm - 20) // 2
print('Resizing to font '+str(fontHeight))
# calculate the best font to use (use int rounding)
bestStyle = fontStyle[10] # use min size as the fallback
if fontHeight < 10: pass # the min size
elif fontHeight >= 50: # the max size
bestStyle = fontStyle[50]
else: # everything in between
bestFitFont = (fontHeight // 5) * 5
bestStyle = fontStyle[bestFitFont]
# set the style on the button
self.mutantButton['style'] = bestStyle
root = Tk()
root.title('Alice in Pythonland')
# make a dictionary of sized font styles in the range of interest.
fontStyle = {}
for font in range(10, 51, 5):
styleName = str(font)+'.TButton'
fontName = ' '.join(['helvetica', str(font), 'bold'])
fontStyle[font] = styleName
Style().configure(styleName, font=fontName)
# run the app
app = ButtonApp(master=root)
app.mainloop()
root.destroy()

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