from django.http import HttpResponse, Http404, JsonResponse
from django.forms.models import model_to_dict
import json
from .models import Continent, Country
def continent_json(request, continent_code):
""" Write your answer in 7.2 here. """
try:
print("CONTINENT QuerySet: ", Continent.objects.filter(
code__exact=continent_code).values("countries"))
continent_data = json.dumps( list(Continent.objects.filter(
code__exact=continent_code).values("countries") ) )
print("CONTINENT JSON: ",continent_data)
except Continent.DoesNotExist:
raise Http404("Requested continent does not exist.")
# If JSONP
if "callback" in request.GET:
continent_data = "{}({})".format(
request.GET["callback"],
continent_data
)
return HttpResponse(continent_data)
# Normal JSON
return HttpResponse(continent_data, content_type="application/json")
def country_json(request, continent_code, country_code):
""" Write your answer in 7.2 here. """
try:
#print("COUNTRY_OBJECT: "Country.objects.filter(code__exact=country_code).values())
print("MODEL_LIST: ",list(Country.objects.filter(code__exact=country_code).values("capital","population","area")))
country_data = json.dumps( list(Country.objects.filter(
code__exact=country_code).values("code","name") ) )
print("COUNTRY DATA: ", country_data)
except Country.DoesNotExist:
raise Http404("Requested country does not exist.")
# If JSONP
if "callback" in request.GET:
country_data = "{}({})".format(
request.GET["callback"],
country_data
)
return HttpResponse(country_data)
# Normal JSON
return HttpResponse(country_data, content_type="application/json")
是否支持根据bin值数组创建直方图？我想绘制一个bin值数组，以在新样本到达时更新图表。我需要在此图表上支持多个系列，并在可能的情况下对其进行动态更新。可以使用jFreeChart和SimpleHistogramDataset完成吗？
我知道我可以使用允许动态更新的SimpleHistogramBin，但是我没有一次尝试两个数据集。我也想知道普通的SimpleHistogramDataset是否允许动态更新，我有点不这样做，因为您必须预先指定values数组参数。