# Using rose to plot polar histogram

Hi there,

I have a list of azimuths that I want to plot as a simple polar histogram, only considering azimuths (i.e. ignoring length). I can’t figure out the syntax to do this. I currently have something like this:

``````fig=pygmt.Figure()

fig.rose(
data=azimuths, # this is just a list
scale='u',
sector='10',
region=[0,1000,0,360],
diameter='7.5c',
frame=["x100g50", "y30g30", "+gwhite"],
color='lightblue',
pen='1p'
)

fig.show()
``````

Maybe you still need to provide a list of lengths with the same value? I don’t use `rose`, but after playing around with Rose diagram — PyGMT, I got this to work:

``````import pygmt

fig = pygmt.Figure()

azimuths: list = [20, 40, 60]
lengths: list = len(azimuths) * [0.001]  # all columns the same length

fig.rose(
azimuth=azimuths,
length=lengths,
scale="u",
sector=2,
# specify the "region" of interest in the (r,azimuth) space
# [r0, r1, az0, az1], here, r0 is 0 and r1 is 1000, for azimuth, az0 is 0
# and az1 is 360 which means we plot a full circle between 0 and 360 degrees
region=[0, 1, 0, 360],
# set the diameter of the rose diagram to 7.5 cm
diameter="7.5c",
# use red3 as color fill for the sectors
color="red3",
# define the frame with ticks and gridlines every 0.2
# length unit in radial direction and every 30 degrees
# in azimuthal direction, set background color to white
frame=["x0.2g0.2", "y30g30", "+gwhite"],
# use a pen size of 1p to draw the outlines
pen="1p",
)

fig.show()
``````

produces:

1 Like

Thanks @weiji14! That works well