Matplotlib output to PDF for Corel Draw

问题:

Update: The fonts issue was actaully solved by using rc("pdf", fonttype=42) but unfortunately it is combined with another - whenever is used any type of marker I tried CorelDraw comes with error "File is corrupted".

When I output my charts from Matplotlib into PDF I am not able to open it in Corel Draw. I highly suspect that the major issue might be with texts / fonts.

Simple code example which I need update to make PDF with text and markers import correctly in Corel Draw:

from matplotlib.backends.backend_pdf import PdfPages
import matplotlib.pyplot as plt
from matplotlib import rc
rc("pdf", fonttype=42)

with PdfPages("simple.pdf") as pdf:
  points_y = points_x = [1,2,3]
  plt.plot(points_x, points_y, marker="o")
  pdf.savefig()
  plt.close()

Example of Corel vs Matplotlib / PDF Reader when not used rc("pdf", fonttype=42) and marker. If marker used PDF doesn't open and CorelDraw says "File is corrupted".

回答1:

It turned out there are two important issues which ruins import of Matplotlib generated PDF into CorelDraw.

1. Setting up the font type from the default rc("pdf", fonttype=3) to rc("pdf", fonttype=42)
2. Not using multiple markers. Only one marker per plot allowed! Possible to replace by text. (no pyplot.scatter, not in pyplot.plot etc.). When using any markers in number of 2 or more per plot CorelDraw finds the PDF corrupted and wont open it at all.

Code rewritten to plot only one marker per plot plus only one marker in the legend:

from matplotlib.backends.backend_pdf import PdfPages
import matplotlib.pyplot as plt
from matplotlib import rc
rc("pdf", fonttype=42)

with PdfPages("simple.pdf") as pdf:
    points_y = points_x = [1,2,3]
    plt.plot(points_x, points_y,color="r")
    # plot points one be one otherwise "File is corrupted" in CorelDraw
    # also plot first point out of loop to make appropriate legend
    plt.plot(points_x[0], points_y[0],marker="o",color="r",markerfacecolor="b",label="Legend label")
    for i in range(1,len(points_x)):
        plt.plot(points_x[i], points_y[i],marker="o",markerfacecolor="b")
    plt.legend(numpoints=1) #Only 1 point in legend because in CorelDraw "File is corrupted" if default two or more 
    pdf.savefig()
    plt.close()

As a possible replacement for points (markers) pyplot.text can be used, for my example in question updated code looks like this:

from matplotlib.backends.backend_pdf import PdfPages
import matplotlib.pyplot as plt
from matplotlib import rc
rc("pdf", fonttype=42)

with PdfPages("simple.pdf") as pdf:
    points_y = points_x = [1,2,3]
    plt.plot(points_x, points_y)
    # print points as + symbol
    for i in range(len(points_x)):
        plt.text(points_x[i], points_y[i],"+",ha="center", va="center")
    pdf.savefig()
    plt.close()