10.1.6. Scaling the axes

File 06-scaling.py in folder demo/plotting/

import pyopus.plotter as pyopl
from numpy import arange, sin, cos, exp, pi, e

if __name__ == '__main__':
	# Initialize gui thread, clean up. 
	pyopl.init()
	pyopl.close()

	# Plot data - sin(x), cos(x), exp(x/pi) .. for x in [0, 2pi] with 0.2 step. 
	x = arange(0.0, 2*pi, 0.2)
	y1 = sin(x)
	y2 = cos(x)
	y3 = exp(x/pi)
	
	# Plot window
	f1=pyopl.figure(windowTitle="Scaling", figpx=(800,400), dpi=100)
	
	# Lock GUI
	pyopl.lock(True)
	
	# Check if figure is alive
	if pyopl.alive(f1):
		# Create 2 subplots, horizontal stack of 2
		ax1=f1.add_subplot(1,2,1)
		ax2=f1.add_subplot(1,2,2)
		
		# First axes
		ax1.plot(x, y1, '-o', label='sin(x)', color=(1,0,0))
		ax1.plot(x, 2*y1, '-o', label='2sin(x)', color=(1,0,0))
		ax1.grid(True)
		ax1.set_xlabel('x')
		ax1.set_ylabel('sin(x), 2sin(x)')
		ax1.set_title('y limits = autoscale + 20%')
		
		# Get y limits
		yl=ax1.get_ylim()
		print("y limits: "+str(yl))
		# Limits are set as two positional arguments, expand by 20%
		ax1.set_ylim(yl[0]*1.2, yl[1]*1.2)
		
		# Second axes
		ax2.plot(x, y1, '-', label='sin(x)', color=(1,0,0))
		ax2.plot(x, y2, '-', label='cos(x)', color=(0,1,0))
		ax2.grid(True)
		ax2.set_xlabel('x')
		ax2.set_ylabel('sin(x), cos(x)')
		ax2.set_title('Manual x,y scale, then autoscale y')
		
		# Set x and y limits
		ax2.set_xlim(3.5, 4.5)
		ax2.set_ylim(-4.0, 4.0)
		
		# Autoscale only y
		ax2.autoscale(axis='y')
		
		# Draw figure on screen
		pyopl.draw(f1)
		
	# Unlock GUI
	pyopl.lock(False)
	
	# Handle keyboard interrupts properly. 
	pyopl.join()