如何获得emf/wmf格式的matplotlib图？

Question

我如何才能获得emf或wmf文件的matplotlib图，这些文件在MS Office (Word和PowerPoint)中可用作矢量图形？

我尝试过导出到svg，并使用Inkscape和LibreOffice绘图转换为emf，但这两个选项似乎都会导致图像质量的下降，从而导致光栅图像。

我也尝试过导出到pdf，并转换到emf/wmf，但这也有同样的问题。

Answer 1

下面是我创建WMF和SVG的解决方案。您可以安装Inkscape并使用以下类，“SaveAndClosePlot”创建SVG，然后使用它转换为WMF的Inkscape。TestPlot函数可以根据您的需要定制。

import os
from pathlib import Path
from ConfigParserM import logging
import subprocess
from matplotlib import pyplot as plt


class SVG_WMF_Plot:

    def __init__(self):
        self.__folderNameGraph = 'Graphs'
        self.__WMF_SVGSaving = True
        self.__inkScapePath = "C://Program Files//inkscape//inkscape.exe"
        self.__figureDPI = 500

    def getRootDirectory(self):
        try:
            return Path(os.path.dirname(os.path.realpath('__file__')))

        except Exception as e:
            logging.exception(e)
            raise

    def getAddressTo(self, Main=None, FolderName=None, FileName=None, Extension=None):
        try:
            if Main is None:
                Main = self.getRootDirectory()
            if FolderName:
                Path1 = Path(Main) / Path(FolderName)
            else:
                Path1 = Path(Main)

            if not os.path.exists(Path1):
                os.makedirs(Path1)
            if FileName:
                if Extension:
                    File_Address = Path1 / Path(FileName + "." + Extension)
                else:
                    File_Address = Path1 / Path(FileName)
            else:
                File_Address = Path1
            return File_Address

        except Exception as e:
            logging.exception(e)
            raise

    def TestPlot(self):
        try:

            fig, ax1 = plt.subplots()
            x = [1, 2]
            y = [1, 2]
            F1 = 'test'
            ax1.plot(x, y)
            self.SaveAndClosePlot(folderName=self.__folderNameGraph, fileName=F1)


        except Exception as e:
            logging.exception(e)
            raise

    def SaveAndClosePlot(self, folderName, fileName):
        try:
            Address = self.getAddressTo(FolderName=self.__folderNameGraph + f"\{folderName}", FileName=fileName, Extension="jpg")
            plt.savefig(Address, format='jpg', dpi=self.__figureDPI, bbox_inches='tight')

            if self.__WMF_SVGSaving:
                Address = self.getAddressTo(FolderName=self.__folderNameGraph + f"\{folderName}", FileName=fileName, Extension="svg")
                plt.savefig(Address, format='svg', dpi=self.__figureDPI, bbox_inches='tight')
                # add removing SVG if needed

                AddressWMF = self.getAddressTo(FolderName=self.__folderNameGraph + f"\{folderName}", FileName=fileName, Extension="wmf")
                subprocess.call([self.__inkScapePath, str(Address.resolve()), '--export-wmf', str(AddressWMF.resolve())])

            plt.clf()
            plt.close()
        except Exception as e:
            logging.exception(e)
            raise

Answer 2

若要使用Linux将数字保存为matplotlib中的.emf文件，请尝试以下操作：

1. 安装Inkscape (我有在Ubuntu中安装Inkscape 0.92.4 16.04 )。其他版本应该一样工作)
2. 在matplotlib中，将图形保存为.svg，然后通过Inkscape子进程调用将其转换为.emf。例如：

    import numpy as np
    import subprocess
    import matplotlib.pyplot as plt
    
    x = np.arange(2,50,step=2)
    y = x**2
    plt.plot(x,y)
    plt.savefig('y_is_x^2.svg', format='svg', bbox_inches='tight')
    subprocess.call('inkscape y_is_x^2.svg -M y_is_x^2.emf',shell=True)

然后，您可以将.emf图作为图片插入MS Word或PowerPoint中。质量接近.svg。不过，请注意，大型.svg文件可能无法工作。