3

抱歉，如果这个问题很简单，我是使用 Python 和 Basemap 的新手。无论如何，我正在尝试在地图（图表）上绘制 20 场飓风的路径。地图本身和图例完美显示，但飓风的路径却没有。此外，我没有收到任何回溯消息，但我想我知道我的问题可能出在哪里。有人可以告诉我哪里出错了。

这是 csv 文件的示例：

Year, Name, Type, Latitude, Longitude
1957,AUDREY,HU, 21.6, 93.3
1957,AUDREY,HU,22.0,  93.4
1957,AUDREY,HU,22.6,  93.5
1969,AUDREY,HU,28.2,99.6
1957,AUDREY,HU,26.5,93.8
1957,AUDREY,HU,27.9,93.8
1957,AUDREY,HU,29.3,95
1957,AUDREY,HU,27.9,93.8
1957,AUDREY,HU,29.3,93.8
1957,AUDREY,HU,30.7,93.5
1969,CAMILLE,HU, 21.6,99.3
1969,CAMILLE,HU,22.0,98.4
1969,CAMILLE,HU,22.6,90.5
1969,CAMILLE,HU,23.2,93.6

这是我到目前为止的代码：

import numpy as np
from mpl_toolkits.basemap import Basemap
import matplotlib.pyplot as plt
import csv, os, scipy
import pandas
from PIL import *


data = np.loadtxt('louisianastormb.csv',dtype=np.str,delimiter=',',skiprows=1)
'''print data'''
fig = plt.figure(figsize=(12,12))

ax = fig.add_axes([0.1,0.1,0.8,0.8])

m = Basemap(llcrnrlon=-100.,llcrnrlat=0.,urcrnrlon=-20.,urcrnrlat=57.,
            projection='lcc',lat_1=20.,lat_2=40.,lon_0=-60.,
            resolution ='l',area_thresh=1000.)

m.bluemarble()
m.drawcoastlines(linewidth=0.5)
m.drawcountries(linewidth=0.5)
m.drawstates(linewidth=0.5)

# Creates parallels and meridians
m.drawparallels(np.arange(10.,35.,5.),labels=[1,0,0,1])
m.drawmeridians(np.arange(-120.,-80.,5.),labels=[1,0,0,1])
m.drawmapboundary(fill_color='aqua')
color_dict = {'AUDREY': 'red', 'ETHEL': 'white', 'BETSY': 'yellow','CAMILLE': 'blue', 'CARMEN': 'green','BABE': 'purple', }


colnames = ['Year','Name','Type','Latitude','Longitude']
data = pandas.read_csv('louisianastormb.csv', names=colnames)
names = list(data.Name)
lat = list(data.Latitude)
long = list(data.Longitude)
colorName = list(data.Name)
#print lat
#print long
lat.pop(0)
long.pop(0)
colorName.pop(0)
latitude= map(float, lat)
longitude = map(float, long)
x, y = m(latitude,longitude)
#Plots points on map
for colorName in color_dict.keys():
    plt.plot(x,y,linestyle ='-',label=colorName,color=color_dict[colorName], linewidth=5 )
    lg = plt.legend()
    lg.get_frame().set_facecolor('grey')
plt.show()
4

2 回答 2

5

两个（好吧，我撒谎了，应该存在）你的代码有问题

i，您的输入经度应该是负数，以在您为底图定义的边界内，因此在转换为 x 和 y 之前添加它

longitude = [-i for i in longitude]

ii，你的坐标转换线不对，你应该在参数列表中交换 lon 和 lat

x, y = m(longitude, latitude)

代替

x, y = m(latitude,longitude)

编辑：

好的，OP在评论中发布的第二个问题，请检查下面的完整代码并注意我所做的与您相比所做的更改

# Last-modified: 21 Oct 2013 05:35:16 PM

import numpy as np
from mpl_toolkits.basemap import Basemap
import matplotlib.pyplot as plt
import csv, os, scipy
import pandas
from PIL import *


data = np.loadtxt('louisianastormb.csv',dtype=np.str,delimiter=',',skiprows=1)
'''print data'''
fig = plt.figure(figsize=(12,12))

ax = fig.add_axes([0.1,0.1,0.8,0.8])

m = Basemap(llcrnrlon=-100.,llcrnrlat=0.,urcrnrlon=-20.,urcrnrlat=57.,
            projection='lcc',lat_1=20.,lat_2=40.,lon_0=-60.,
            resolution ='l',area_thresh=1000.)

m.drawcoastlines(linewidth=0.5)
m.drawcountries(linewidth=0.5)
m.drawstates(linewidth=0.5)
# m.bluemarble(ax=ax)

# Creates parallels and meridians
m.drawparallels(np.arange(10.,35.,5.),labels=[1,0,0,1])
m.drawmeridians(np.arange(-120.,-80.,5.),labels=[1,0,0,1])
m.drawmapboundary(fill_color='aqua')
color_dict = {'AUDREY': 'red', 'ETHEL': 'white', 'BETSY': 'yellow','CAMILLE': 'blue', 'CARMEN': 'green','BABE': 'purple', }

colnames = ['Year','Name','Type','Latitude','Longitude']
data = pandas.read_csv('louisianastormb.csv', names=colnames)
names = list(data.Name)
lat = list(data.Latitude)
long = list(data.Longitude)
colorNames = list(data.Name)
#print lat
#print long
lat.pop(0)
long.pop(0)
colorNames.pop(0)
latitude= map(float, lat)
longitude = map(float, long)
# added by nye17
longitude = [-i for i in longitude]
# x, y = m(latitude,longitude)
x, y = m(longitude,latitude)
# convert to numpy arrays
x = np.atleast_1d(x)
y = np.atleast_1d(y)
colorNames = np.atleast_1d(colorNames)
#Plots points on map
for colorName in color_dict.keys():
    plt.plot(x[colorName == colorNames],y[colorName == colorNames],linestyle ='-',label=colorName,color=color_dict[colorName], linewidth=5 )
    lg = plt.legend()
    lg.get_frame().set_facecolor('grey')
plt.show()

在此处输入图像描述

于 2013-10-21T20:56:00.157 回答
1

我认为你的困难在底图中并不像在绘图中那么大。您需要找到飓风 Z 上对应的 x/y 点，而不是绘制整个 x/y 数据集。然后仅绘制具有特定颜色 c 的那些点。然后找到下一个飓风等对应的点...

下面，虽然不使用 Basemap 数据结构，但应该为基于某些选择器向量绘制点的子集提供一个起点。

#given a list of x,y coordinates with a  label we'll plot each line individually

#first construct some points to plot
x1 = [1,1.1,1.2,1.3, 2.0,2.2,2.3, 4,3.9,3.8,3.7]
y1 = [5,5.1,5.2,5.3, 6.0,6.2,6.3, 2,2.1,2.2,2.3]
pointNames = []
#generate some labels
pointNames.extend(['a']*4)
pointNames.extend(['b']*3)
pointNames.extend(['c']*4)

#make things easy by casting to numpy arrays to allow for easier indexing
x1 = numpy.array(x1)
y1 = numpy.array(y1)
pointNames = numpy.array(pointNames)

for elem in ['a','b','c']:
  selector = pointNames==elem
  subsetX = x1[selector]
  subsetY = y1[selector]
  #now plot subsetX vs subsetY in color Z
  plot(subsetX,subsetY,'*-')

show()
于 2013-10-21T20:46:09.320 回答