eStatAPI_eStatAPI.go

 package estatapi

import (
	"encoding/json"
	"io/ioutil"
	"log"
	"net/http"

	"../config"
)

type Estat struct {
	GET_STATS_DATA GetStatsData
}

type GetStatsData struct {
	RESULT           interface{}
	PARAMETER        interface{}
	STATISTICAL_DATA StatisticalData
}

type StatisticalData struct {
	RESULT_INF interface{}
	TABLE_INF  interface{}
	CLASS_INF  interface{}
	DATA_INF   DataInf
}

type DataInf struct {
	NOTE  interface{}
	VALUE []Value
}

type Value struct {
	Cat01  string `json:"@cat01"`
	Cat02  string `json:"@cat02"`
	Cat03  string `json:"@cat03"`
	Area   string `json:"@area"`
	Time   string `json:"@time"`
	Unit   string `json:"@unit"`
	Dollar string `json:"$"`
}

func Get() Estat {

	url := "http://api.e-stat.go.jp/rest/2.0/app/json/getStatsData?appId=" + config.AppId + "&statsDataId=0003104181"

	resp, err := http.Get(url)
	if err != nil {
		log.Fatal(err)
	}
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		log.Fatal(err)
	}
	var e Estat
	if err := json.Unmarshal([]byte(body), &e); err != nil {
		panic(err)
	}

	return e

}

eStatAPI_main.go

package main

import (
	"strconv"

	"github.com/gonum/plot"
	"github.com/gonum/plot/plotter"
	"github.com/gonum/plot/plotutil"
	"github.com/gonum/plot/vg"

	"./estatapi"
)

func main() {

	resp := estatapi.Get()
	values := resp.GET_STATS_DATA.STATISTICAL_DATA.DATA_INF.VALUE
	m, f := format(values)

	male := plotter.Values{m["0"], m["20"], m["40"], m["60"], m["80"], m["100"]}
	female := plotter.Values{f["0"], f["20"], f["40"], f["60"], f["80"], f["100"]}

	p, err := plot.New()
	if err != nil {
		panic(err)
	}
	p.Title.Text = "male&female"
	p.X.Label.Text = "old"
	p.Y.Label.Text = "number(thousand)"

	w := vg.Points(20)

	maleBars, err := plotter.NewBarChart(male, w)
	if err != nil {
		panic(err)
	}
	maleBars.LineStyle.Width = vg.Length(0)
	maleBars.Color = plotutil.Color(0)
	maleBars.Offset = -w

	femaleBars, err := plotter.NewBarChart(female, w)
	if err != nil {
		panic(err)
	}
	femaleBars.LineStyle.Width = vg.Length(0)
	femaleBars.Color = plotutil.Color(1)

	p.Add(maleBars, femaleBars)
	p.Legend.Add("male", maleBars)
	p.Legend.Add("female", femaleBars)
	p.Legend.Top = true
	p.Legend.Left = true
	p.NominalX("0", "20", "40", "60", "80", "100over")

	if err := p.Save(5*vg.Inch, 3*vg.Inch, "graf.png"); err != nil {
		panic(err)
	}
}

func format(values []estatapi.Value) (map[string]float64, map[string]float64) {
	male := make(map[string]float64)
	female := make(map[string]float64)
	for _, v := range values {
		if v.Cat02 == "001" {
			if v.Cat01 == "002" {
				switch v.Cat03 {
				case "01001":
					male["0"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01021":
					male["20"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01041":
					male["40"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01061":
					male["60"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01081":
					male["80"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01101":
					male["100"], _ = strconv.ParseFloat(v.Dollar, 64)
				}
			} else if v.Cat01 == "003" {
				switch v.Cat03 {
				case "01001":
					female["0"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01021":
					female["20"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01041":
					female["40"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01061":
					female["60"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01081":
					female["80"], _ = strconv.ParseFloat(v.Dollar, 64)
				case "01101":
					female["100"], _ = strconv.ParseFloat(v.Dollar, 64)
				}
			}
		}
	}
	return male, female
}