Vectors

The pygmt.Figure.plot method can plot cartesian, circular, and geographic vectors. The style parameter controls vector attributes as in GMT6

Out:

<IPython.core.display.Image object>

import numpy as np
import pygmt


# Create a plot with 15x15 cm basemap, Mercator projection (M) over the continental US
region=[-127, -64, 24, 53]
fig=pygmt.Figure()
fig.coast(region=region, projection="M15c", B="10.0", N='1', A='4000', W='0.25p,black')


# plot math angle arcs with different radii
x=-110
y=37
startdir=90
stopdir=180
radius=1.8
pen="1.5p,black"
arcstyles = np.repeat("m0.5c+ea", 7)
for arcstyle in arcstyles:
    data = np.array([[x, y, radius, startdir, stopdir]])
    fig.plot(data=data,
             style=arcstyle,
             color="red3",
             pen=pen)
    stopdir+=40
    radius-=0.2
fig.text(text="CIRCULAR", x=-112, y=44.2, font="13p,Helvetica-Bold,black", fill='white')


# plot cartesian vectors with different lengths
x=np.linspace(-100, -100, 12)   # x vector coordinates
y=np.linspace(33,42.5, 12)      # y vector coordinates
xvec = np.linspace(1, 5, 12)    # dx vector data
yvec = np.zeros(np.shape(y))    # dy vector data
style = 'v0.2+e+a40+gred+h0+p1p,red+z0.35'
pen='1.0p,red'
fig.plot(x=x, y=y, style=style, pen=pen, direction=[xvec, yvec])
fig.text(text="CARTESIAN", x=-95, y=44.2, font="13p,Helvetica-Bold,red", fill='white')


# plot geographic vectors using endpoints
NYC = [-74.0060, 40.7128]
CHI = [-87.6298, 41.8781]
SEA = [-122.3321, 47.6062]
NO =  [-90.0715, 29.9511]
style = '=0.5+e+a30+gblue+h0.5+p1p,blue+s'  # = for geographic coordinates, +s for coord end points
pen='1.0p,blue'
data = np.array([[NYC[0], NYC[1], CHI[0], CHI[1]]]);
data = np.vstack((data, np.array([[NYC[0], NYC[1], SEA[0], SEA[1]]])));
data = np.vstack((data, np.array([[NYC[0], NYC[1], NO[0], NO[1]]])));
fig.plot(data=data, style=style, pen=pen)
fig.text(text="GEOGRAPHIC", x=-74.5, y=44.2, font="13p,Helvetica-Bold,blue", fill='white')
fig.show()