回答此问题可获得 20 贡献值,回答如果被采纳可获得 50 分。
<p>我尝试用matplotlib绘制gfs天气模型的输出,使用pygrib保存数据,这些数据保存在grib文件中。几乎一切正常,输出如下:</p>
<p><img src="https://i.stack.imgur.com/imAbh.png" alt="enter image description here"/></p>
<p>程序似乎没有用0度的数据来缩小359.5到360度之间的差距。如果数据是在一个常规列表或其他东西中,我将使用0°的数据,并通过附加列表将其保存360°。我见过有人对非pygrib数据有同样的问题。
如果您知道如何更改pygrib数据(不幸的是,常规操作对pygrib数据不起作用)或如何使matplotlib缩小差距,您将真正帮助我解决这个问题。也许函数“addcyclic”能帮上忙,但我不知道怎么做。在</p>
<p>编辑:我解决了问题,看看我的答案。在</p>
<p>下面是产生问题的代码:</p>
<pre><code>#!/usr/bin/python3
import os, sys, datetime, string
from abc import ABCMeta, abstractmethod
import numpy as np
import numpy.ma as ma
from scipy.ndimage.filters import minimum_filter, maximum_filter
import pygrib
from netCDF4 import <a href="https://www.cnpython.com/pypi/dataset" class="inner-link">dataset</a>
from pylab import *
import matplotlib.pyplot as plt
from mpl_toolkits.basemap import Basemap, addcyclic, shiftgrid
import laplaceFilter
import mpl_util
class Plot(Basemap):
def __init__(self, basemapParams):
super().__init__(**basemapParams)
self.layers = []
def addLayer(self, layer):
self.layers.<a href="https://www.cnpython.com/list/append" class="inner-link">append</a>(layer)
def plot(self, data):
for layer in self.layers:
layer.plot(self, data)
plt.title('Plot')
plt.show()
class Layer(metaclass=ABCMeta):
def __init__(self):
pass
@abstractmethod
def plot(self, plot, data):
return NotImplemented
class BackgroundLayer(Layer):
def __init__(self, bgtype, coords):
#possible bgtype values: borders, topo, both
self.bgtype = bgtype
self.lonStart = coords[0]
self.lonEnd = coords[1]
self.latStart = coords[2]
self.latEnd = coords[3]
def plot(self, plot, data):
[...]
def findSubsetIndices(self,min_lat,max_lat,min_lon,max_lon,lats,lons):
[...]
class LegendLayer(Layer):
def __init__(self):
pass
class GribDataLayer(Layer, metaclass=ABCMeta):
def __init__(self, varname, level, clevs, cmap, factor):
self.varname = varname
self.level = level
self.clevs = clevs
self.cmap = cmap
self.factor = factor
def plot(self, plot, data):
#depending on the height we want to use, we have to change the index
indexes = {1000:0, 2000:1, 3000:2, 5000:3, 7000:4, 10000:5, 15000:6, 20000:7, 25000:8, 30000:9,
35000:10, 40000:11, 45000:12, 50000:13, 55000:14, 60000:15, 65000:16, 70000:17,
75000:18, 80000:19, 85000:20, 90000:21, 92500:22, 95000:23, 97500:24, 100000:25, 0:0}
selecteddata = data.select(name = self.varname)[indexes[self.level]]
lats, lons = selecteddata.latlons()
layerdata = selecteddata.values*self.factor
x, y = plot(lons, lats) # compute map proj coordinates.
self.fillLayer(plot, x, y, layerdata, self.clevs, self.cmap)
@abstractmethod
def fillLayer(self, plot, x, y, layerdata, clevs, cmap):
return NotImplemented
class ContourLayer(GribDataLayer):
def __init__(self, varname, level, clevs, cmap, factor, linewidth=1.5, fontsize=15,
fmt="%3.1f", inline=0,labelcolor = 'k'):
self.linewidth = linewidth
self.fontsize = fontsize
self.fmt = fmt
self.inline = inline
self.labelcolor = labelcolor
super().__init__(varname, level, clevs, cmap, factor)
def fillLayer(self, plot, x, y, layerdata, clevs, cmap):
# contour data over the map.
cs = plot.contour(x,y,layerdata,clevs,colors = cmap,linewidths = self.linewidth)
plt.clabel(cs, clevs, fontsize = self.fontsize, fmt = self.fmt,
inline = self.inline, colors = self.labelcolor)
if self.varname == "Pressure reduced to MSL":
self.plotHighsLows(plot,layerdata,x,y)
def plotHighsLows(self,plot,layerdata,x,y):
[...]
class ContourFilledLayer(GribDataLayer):
def __init__(self, varname, level, clevs, cmap, factor, extend="both"):
self.extend = extend
super().__init__(varname, level, clevs, cmap, factor)
def fillLayer(self, plot, x, y, layerdata, clevs, cmap):
# contourfilled data over the map.
cs = plot.contourf(x,y,layerdata,levels=clevs,cmap=cmap,extend=self.extend)
#cbar = plot.colorbar.ColorbarBase(cs)
[...]
ger_coords = [4.,17.,46.,56.]
eu_coords = [-25.,57.,22.,70.]
### Choose Data
data = pygrib.open('gfs.t12z.mastergrb2f03')
### 500hPa Europe
coords = eu_coords
plot1 = Plot({"projection":"lcc","resolution":"h","rsphere":(6378137.00,6356752.3142), "area_thresh": 1000.,
"llcrnrlon":coords[0],"llcrnrlat":coords[2],"urcrnrlon":coords[1],"urcrnrlat":coords[3],
"lon_0":(coords[0]+coords[1])/2.,"lat_0":(coords[2]+coords[3])/2.})
clevs = range(480,600,4)
cmap = plt.cm.nipy_spectral
factor = .1
extend = "both"
level = 50000
layer1 = ContourFilledLayer('Geopotential Height', level, clevs, cmap, factor, extend)
clevs = [480.,552.,600.]
linewidth = 2.
fontsize = 14
fmt = "%d"
inline = 0
labelcolor = 'k'
layer2 = ContourLayer('Geopotential Height', level, clevs, 'k', factor, linewidth, fontsize, fmt, inline, labelcolor)
level = 0
clevs = range(800,1100,5)
factor = .01
linewidth = 1.5
inline = 0
labelcolor = 'k'
layer3 = ContourLayer('Pressure reduced to MSL', level, clevs, 'w', factor, linewidth, fontsize, fmt, inline, labelcolor)
plot1.addLayer(BackgroundLayer('borders', coords))
plot1.addLayer(layer1)
plot1.addLayer(layer2)
plot1.addLayer(layer3)
plot1.plot(data)
</code></pre>