Python Matplotlib: How do I save (in pdf) all the graphs I create in a loop?

[JaneTan]

Hi,

Refer to the entire code appended at the end. Thanks

1) I meet with "Cannot assign to operator (pyflakes E)" when I try to assign a variable(j) to the name of another variable

1	'fig' + str(j), 'ax' + str(j) = plt.subplots()

2) How can I create a loop to save all the plots I created in the loop to a single pdf file?
Thank you

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import xlrd import openpyxl import numpy as np import matplotlib.pyplot as plt from matplotlib.backends.backend_pdf import PdfPages file_location = "C:/Users/Desktop/Sample1.xlsx"   j=0 wb = xlrd.open_workbook(file_location) ws = wb.sheet_by_index(0)     x1 = [int(ws.cell_value(i, 0)) for i in range(1,ws.nrows)] x2 = [int(ws.cell_value(i, 0)) for i in range((ws.nrows-10),ws.nrows)]   for col in range(1,ws.ncols,4):     j+=j       y1 = [ws.cell_value(i, col) for i in range(1,ws.nrows)]     #plt.figure(0)       'fig' + str(j), 'ax' + str(j) = plt.subplots()           'ax'+str(j).plot(x1, y1)   pp = PdfPages('C:/Users/Desktop/Sample1.pdf') pp.savefig(fig1) pp.savefig(fig2) pp.close()       del pp

[Larz60+]

Here's a simple example:

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import matplotlib.pyplot as plt import numpy as np   np.random.seed(19680801) data = np.random.randn(2, 100)   fig, axs = plt.subplots(2, 2, figsize=(5, 5)) axs[0, 0].hist(data[0]) axs[1, 0].scatter(data[0], data[1]) axs[0, 1].plot(data[0], data[1]) axs[1, 1].hist2d(data[0], data[1])   plt.show() plt.savefig("mypdf.pdf")