pywcat 0.3.0

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pywcat

A set of simple python helpers for sending images and plots to wcat for preview.

This is a useful alternative to jupyter for previews on a remote machine.

Setup

First, make sure you are running a wcat server https://github.com/olivercoad/wcat/#setup and can access it in your browser.

Once you have a wcat server running (on a local or remote machine), install pywcat.

pip install pywcat

Usage

See sample.py for usage example.

matplotlib

Plots are displayed with SVG format for the best quality.

import matplotlib.pyplot as plt
import pywcat.matplotlib as wplt

plt.plot([1,3,2,4])
plt.ylabel('some more number stuff')
plt.title("Matplotlib with wcat")

wplt.show("Example Matplotlib plot")

The **kwargs on wplt.show are passed down to matplotlib.pyplot.savefig to allow for more control over output.

bokeh

from bokeh.plotting import figure, output_file
from pywcat.bokeh import show

# prepare some data
x = [1, 2, 3, 4, 5]
y = [6, 7, 2, 4, 5]

# create a new plot with a title and axis labels
p = figure(title="Bokeh with wcat", x_axis_label='x', y_axis_label='y')

# add a line renderer with legend and line thickness
p.line(x, y, legend_label="Temp.", line_width=2)

# show the results
show(p, "Example Bokeh plot")

Pillow

Defaults to PNG format.

from PIL import Image, ImageDraw, ImageFont
from pywcat.PIL import show

img = Image.new('RGB', (200, 60), color = (73, 109, 137))

d = ImageDraw.Draw(img)
d.text((10,10), "Pillow PIL with wcat as PNG", fill=(255, 255, 0))

show(img, "PIL PNG")

Use JPEG format for faster load time

show(img, "PIL JPEG", format="JPEG")

Usage on a remote machine

It is recommended to send previews on the same machine that the server is running.

If you follow the instructions for using wcat on a remote machine and the wcat server accessible on http://localhost:8085 then it will work by default.

Otherwise, this can be changed for pywcat with the WCATSERVER environment variable:

export WCATSERVER=http://localhost:8085
python sample.py

or by setting the value in python:

import pywcat.server
pywcat.server.wcatserver = "http://localhost:8085"