Julia: Bar chart from JSON data using StatsPlots

This page shows one way to use Julia and the StatsPlots package(s) to create a simple bar chart.

Here are links to the topic series of representing and processing data.

R examples:

Python examples:

JavaScript and D3 examples:

JavaScript: SVG bar chart using D3

Julia examples:

Julia: Bar chart from JSON data using StatsPlots (this page)

... more to be added ...

Julia packages can be installed from REPL loop or from the command line. Here is one way to install the Julia package(s) StatsPlots from the Windows command line.

"D:\E\julia-1.5.3\bin\julie.exe" -e "using Pkg; Pkg.add(\"StatsPlots\")"

The backslash quotes in the quoted text are important. The path you use should include the installed version of Julia. The one here is D:\E\julia-1.5.3\bin. Julia installs any needed dependencies, so the installation could take a while.

From the REPL command line, the following can be used (right square bracket followed by command).

] add StatsPlots

Julia packages can be installed from REPL loop or from the command line. Here is one way to install the Julia package(s) JSON from the Windows command line.

"D:\E\julia-1.5.3\bin\julie.exe" -e "using Pkg; Pkg.add(\"JSON\")"

The backslash quotes in the quoted text are important. The path you use should include the installed version of Julia. The one here is D:\E\julia-1.5.3\bin. Julia installs any needed dependencies, so the installation could take a while.

From the REPL command line, the following can be used (right square bracket followed by command).

] add JSON

Here is one possible JSON way to represent data as a list of lists.

[ ["a",59900], ["b",11302], ["c",14311], ["d",34483], ["e",95247], ["f",17852], ["g",13528], ["h",62509], ["i",46347], ["j",2321], ["k",4449], ["l",25939], ["m",19154], ["n",51311], ["o",54741], ["p",9918], ["q",183], ["r",37468], ["s",44630], ["t",72396], ["u",20651], ["v",7458], ["w",18376], ["x",376], ["y",14814], ["z",234] ]

Here is the Julia code to read the above JSON data file and output the results. Here is the Julia code [#1]

using Printf
using JSON
jsonFs1 = "./letters1.json"
println(@sprintf("Read JSON data in \"%s\".",jsonFs1));
jsonText1 = read(jsonFs1,String)
dataList1 = JSON.parse(jsonText1)
println("Process data into needed form.");
nameData1 = []
valueData1 = []
for item1 in dataList1
	xValue1 = item1[1]
	yValue1 = item1[2]
	push!(nameData1,xValue1)
	push!(valueData1,yValue1)
	end
imageFs2 = "./jlx32-1-01.png"
println(@sprintf("Save image to \"%s\".",imageFs2));

Here is the output of the Julia code.

Read JSON data in "./letters1.json".
Process data into needed form.
Save image to "./jlx32-1-01.png".

This is a simple bar chart for the present purposes. Future topics will cover how to make it look nicer.