Question

Hi I am trying to plot this using matplotlib’s step function

from matplotlib.pyplot import step, show, xlim

time = [0.0, 0.0, 0.0, 25.3039, 25.5539, 25.8049, 45.8699, 46.1209, 46.3719, 46.6229, 63.1719, 63.4239, 63.6749, 79.9779, 80.2289, 80.4799, 80.7309]
value = ['0', '0', '0', '93', '940', '951', '940', '437', '422', '421', '423', '598', '605', '192', '3', '1', '0']

xlim(0, 145)
step(time,value)

show()

I am hoping the step function will show the plot to be 0 and starts at 93 from time 25.3039. Instead I see value 93 from time 0 as shown in the graph. I need to keep the timeline to start from 0 so I can’t really change my xlim to start from 25.3039

What should I do to fix the issue? Any help will be appreciated!

Thanks!

Answer 1

You need to set where step should step (doc). The default is that the locations are interpreted as the right edge, you want the locations interpreted as the left edge.

step(time,value,where='post')

See Step function in matplotlib for a longer explanation/example.