# Carpet Contour Plot in Julia

How to make carpet contour plots in Julia with Plotly.

### Basic Carpet Plot

Set the x and y coordinates, using x and y attributes. If x coordinate values are omitted a cheater plot will be created. To save parameter values use a and b attributes. To make changes to the axes, use aaxis or baxis attributes. For a more detailed list of axes attributes refer to julia reference.

using PlotlyJS

plot(carpet(
a=[0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3],
b=[4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6],
x=[2, 3, 4, 5, 2.2, 3.1, 4.1, 5.1, 1.5, 2.5, 3.5, 4.5],
y=[1, 1.4, 1.6, 1.75, 2, 2.5, 2.7, 2.75, 3, 3.5, 3.7, 3.75],
aaxis=attr(
tickprefix="a=",
smoothing=0,
minorgridcount=9,
type="linear"
),
baxis=attr(
tickprefix="b=",
smoothing=0,
minorgridcount=9,
type="linear"
)
))

// TODO: Can"t use end as argument?

using PlotlyJS

trace1 = contourcarpet(
a=[0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3],
b=[4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6],
z=[1, 1.96, 2.56, 3.0625, 4, 5.0625, 1, 7.5625, 9, 12.25, 15.21, 14.0625],
autocontour=false,
contours=attr(
start=1,
size=1
),
contours_end=14,
line=attr(
width=2,
smoothing=0
),
colorbar=attr(
len=0.4,
y=0.25
)
)

trace2 = carpet(
a=[0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3],
b=[4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6],
x=[2, 3, 4, 5, 2.2, 3.1, 4.1, 5.1, 1.5, 2.5, 3.5, 4.5],
y=[1, 1.4, 1.6, 1.75, 2, 2.5, 2.7, 2.75, 3, 3.5, 3.7, 3.75],
aaxis=attr(
tickprefix="a=",
smoothing=0,
minorgridcount=9,
type="linear"
),
baxis=attr(
tickprefix="b=",
smoothing=0,
minorgridcount=9,
type="linear"
)
)

plot([trace1, trace2])

using PlotlyJS, HTTP, JSON

response = HTTP.get("https://raw.githubusercontent.com/bcdunbar/datasets/master/airfoil_data.json")
data = JSON.parse(String(response.body))

trace1 = carpet(
a=data[1]["a"],
b=data[1]["b"],
x=data[1]["x"],
y=data[1]["y"],
baxis=attr(
startline=false,
endline=false,
showticklabels="none",
smoothing=0,
showgrid=false
),
aaxis=attr(
startlinewidth=2,
startline=true,
showticklabels="none",
endline=true,
showgrid=false,
endlinewidth=2,
smoothing=0
)
)

trace2 = contourcarpet(
z=data[2]["z"],
autocolorscale=false,
zmax=1,
name="Pressure",
colorscale="Viridis",
zmin=-8,
colorbar=attr(
y=0,
yanchor="bottom",
titleside="right",
len=0.75,
title="Pressure coefficient, c<sub>p</sub>"
),
contours=attr(
start=-1,
size=0.025,
showlines=false
),
contours_end=1.000,
line=attr(
smoothing=0
),
autocontour=false,
zauto=false
)

trace3 = contourcarpet(
z=data[3]["z"],
opacity=0.300,
showlegend=true,
name="Streamlines",
autocontour=true,
ncontours=50,
contours=attr(
coloring="none"
),
line=attr(
color="white",
width=1
)
)

trace4 = contourcarpet(
z=data[4]["z"],
showlegend=true,
name="Pressure<br>contours",
autocontour=false,
line=attr(
color="rgba(0, 0, 0, 0.5)",
smoothing=1
),
contours=attr(
size=0.250,
start=-4,
coloring="none",
showlines=true
),
contours_end=1.000,
)

trace5 = scatter(
x=data[5]["x"],
y=data[5]["y"],
legendgroup="g1",
name="Surface<br>pressure",
mode="lines",
hoverinfo="skip",
line=attr(
color="rgba(255, 0, 0, 0.5)",
width=1,
shape="spline",
smoothing=1
),
fill="toself",
fillcolor="rgba(255, 0, 0, 0.2)"
)

trace6 = scatter(
x=data[6]["x"],
y=data[6]["y"],
showlegend=false,
legendgroup="g1",
mode="lines",
hoverinfo="skip",
line=attr(
color="rgba(255, 0, 0, 0.3)",
width=1
)
)

trace7 = scatter(
x=data[7]["x"],
y=data[7]["y"],
showlegend=false,
legendgroup="g1",
name="cp",
text=data[7]["text"],
hoverinfo="text",
mode="lines",
line=attr(
color="rgba(255, 0, 0, 0.2)",
width=0
)
)

layout = Layout(
yaxis=attr(
zeroline=false,
range=[-1.800,1.800],
showgrid=false
),
dragmode="pan",
height=700,
xaxis=attr(
zeroline=false,
scaleratio=1,
scaleanchor="y",
range=[-3.800,3.800],
showgrid=false
),
title="Flow over a Karman-Trefftz airfoil",
hovermode="closest",
margin=attr(
r=60,
b=40,
l=40,
t=80
),
width=900
)

plot([trace1, trace2, trace3, trace4, trace5, trace6, trace7], layout)