diff --git a/doc/api/next_api_changes/2019-03-23-AL.rst b/doc/api/next_api_changes/2019-03-23-AL.rst new file mode 100644 index 000000000000..4d5b7e6d2788 --- /dev/null +++ b/doc/api/next_api_changes/2019-03-23-AL.rst @@ -0,0 +1,7 @@ +Deprecations +```````````` + +`.pyplot.plotfile` is deprecated in favor of separately loading and plotting +the data. See :doc:`/gallery/misc/plotfile_demo_sgskip` for various ways to +use pandas or numpy to load data, and pandas or matplotlib to plot the +resulting data. diff --git a/examples/misc/plotfile_demo.py b/examples/misc/plotfile_demo.py deleted file mode 100644 index d55323b1f7c7..000000000000 --- a/examples/misc/plotfile_demo.py +++ /dev/null @@ -1,45 +0,0 @@ -""" -============= -Plotfile Demo -============= - -Example use of ``plotfile`` to plot data directly from a file. -""" - -import matplotlib.pyplot as plt -import matplotlib.cbook as cbook - -fname = cbook.get_sample_data('msft.csv', asfileobj=False) -fname2 = cbook.get_sample_data('data_x_x2_x3.csv', asfileobj=False) - -# test 1; use ints -plt.plotfile(fname, (0, 5, 6)) - -# test 2; use names -plt.plotfile(fname, ('date', 'volume', 'adj_close')) - -# test 3; use semilogy for volume -plt.plotfile(fname, ('date', 'volume', 'adj_close'), - plotfuncs={'volume': 'semilogy'}) - -# test 4; use semilogy for volume -plt.plotfile(fname, (0, 5, 6), plotfuncs={5: 'semilogy'}) - -# test 5; single subplot -plt.plotfile(fname, ('date', 'open', 'high', 'low', 'close'), subplots=False) - -# test 6; labeling, if no names in csv-file -plt.plotfile(fname2, cols=(0, 1, 2), delimiter=' ', - names=['$x$', '$f(x)=x^2$', '$f(x)=x^3$']) - -# test 7; more than one file per figure--illustrated here with a single file -plt.plotfile(fname2, cols=(0, 1), delimiter=' ') -plt.plotfile(fname2, cols=(0, 2), newfig=False, - delimiter=' ') # use current figure -plt.xlabel(r'$x$') -plt.ylabel(r'$f(x) = x^2, x^3$') - -# test 8; use bar for volume -plt.plotfile(fname, (0, 5, 6), plotfuncs={5: 'bar'}) - -plt.show() diff --git a/examples/misc/plotfile_demo_sgskip.py b/examples/misc/plotfile_demo_sgskip.py new file mode 100644 index 000000000000..29bc0c1fac31 --- /dev/null +++ b/examples/misc/plotfile_demo_sgskip.py @@ -0,0 +1,170 @@ +""" +========================= +Plotting data from a file +========================= + +Plotting data from a file is actually a two-step process. + +1. Interpreting the file and loading the data. +2. Creating the actual plot. + +`.pyplot.plotfile` tried to do both at once. But each of the steps has so many +possible variations and parameters that it does not make sense to squeeze both +into a single function. Therefore, `.pyplot.plotfile` has been deprecated. + +The recommended way of plotting data from a file is therefore to use dedicated +functions such as `numpy.loadtxt` or `pandas.read_csv` to read the data. These +are more powerful and faster. Then plot the obtained data using matplotlib. + +Note that `pandas.DataFrame.plot` is a convenient wrapper around Matplotlib +to create simple plots. +""" + +import matplotlib.pyplot as plt +import matplotlib.cbook as cbook + +import numpy as np +import pandas as pd + +############################################################################### +# Using pandas +# ============ +# +# Subsequent are a few examples of how to replace `~.pyplot.plotfile` with +# `pandas`. All examples need the the `pandas.read_csv` call first. Note that +# you can use the filename directly as a parameter:: +# +# msft = pd.read_csv('msft.csv') +# +# The following slightly more involved `pandas.read_csv` call is only to make +# automatic rendering of the example work: + +fname = cbook.get_sample_data('msft.csv', asfileobj=False) +with cbook.get_sample_data('msft.csv') as file: + msft = pd.read_csv(file) + +############################################################################### +# When working with dates, additionally call +# `pandas.plotting.register_matplotlib_converters` and use the ``parse_dates`` +# argument of `pandas.read_csv`:: + +pd.plotting.register_matplotlib_converters() + +with cbook.get_sample_data('msft.csv') as file: + msft = pd.read_csv(file, parse_dates=['Date']) + + +############################################################################### +# Use indices +# ----------- + +# Deprecated: +plt.plotfile(fname, (0, 5, 6)) + +# Use instead: +msft.plot(0, [5, 6], subplots=True) + +############################################################################### +# Use names +# --------- + +# Deprecated: +plt.plotfile(fname, ('date', 'volume', 'adj_close')) + +# Use instead: +msft.plot("Date", ["Volume", "Adj. Close*"], subplots=True) + +############################################################################### +# Use semilogy for volume +# ----------------------- + +# Deprecated: +plt.plotfile(fname, ('date', 'volume', 'adj_close'), + plotfuncs={'volume': 'semilogy'}) + +# Use instead: +fig, axs = plt.subplots(2, sharex=True) +msft.plot("Date", "Volume", ax=axs[0], logy=True) +msft.plot("Date", "Adj. Close*", ax=axs[1]) + + +############################################################################### +# Use semilogy for volume (by index) +# ---------------------------------- + +# Deprecated: +plt.plotfile(fname, (0, 5, 6), plotfuncs={5: 'semilogy'}) + +# Use instead: +fig, axs = plt.subplots(2, sharex=True) +msft.plot(0, 5, ax=axs[0], logy=True) +msft.plot(0, 6, ax=axs[1]) + +############################################################################### +# Single subplot +# -------------- + +# Deprecated: +plt.plotfile(fname, ('date', 'open', 'high', 'low', 'close'), subplots=False) + +# Use instead: +msft.plot("Date", ["Open", "High", "Low", "Close"]) + +############################################################################### +# Use bar for volume +# ------------------ + +# Deprecated: +plt.plotfile(fname, (0, 5, 6), plotfuncs={5: "bar"}) + +# Use instead: +fig, axs = plt.subplots(2, sharex=True) +axs[0].bar(msft.iloc[:, 0], msft.iloc[:, 5]) +axs[1].plot(msft.iloc[:, 0], msft.iloc[:, 6]) +fig.autofmt_xdate() + +############################################################################### +# Using numpy +# =========== + +fname2 = cbook.get_sample_data('data_x_x2_x3.csv', asfileobj=False) +with cbook.get_sample_data('data_x_x2_x3.csv') as file: + array = np.loadtxt(file) + +############################################################################### +# Labeling, if no names in csv-file +# --------------------------------- + +# Deprecated: +plt.plotfile(fname2, cols=(0, 1, 2), delimiter=' ', + names=['$x$', '$f(x)=x^2$', '$f(x)=x^3$']) + +# Use instead: +fig, axs = plt.subplots(2, sharex=True) +axs[0].plot(array[:, 0], array[:, 1]) +axs[0].set(ylabel='$f(x)=x^2$') +axs[1].plot(array[:, 0], array[:, 2]) +axs[1].set(xlabel='$x$', ylabel='$f(x)=x^3$') + +############################################################################### +# More than one file per figure +# ----------------------------- + +# For simplicity of the example we reuse the same file. +# In general they will be different. +fname3 = fname2 + +# Depreacted: +plt.plotfile(fname2, cols=(0, 1), delimiter=' ') +plt.plotfile(fname3, cols=(0, 2), delimiter=' ', + newfig=False) # use current figure +plt.xlabel(r'$x$') +plt.ylabel(r'$f(x) = x^2, x^3$') + +# Use instead: +fig, ax = plt.subplots() +ax.plot(array[:, 0], array[:, 1]) +ax.plot(array[:, 0], array[:, 2]) +ax.set(xlabel='$x$', ylabel='$f(x)=x^3$') + +plt.show() diff --git a/examples/tests/backend_driver_sgskip.py b/examples/tests/backend_driver_sgskip.py index 8878c6273bce..761287e5e292 100644 --- a/examples/tests/backend_driver_sgskip.py +++ b/examples/tests/backend_driver_sgskip.py @@ -212,7 +212,6 @@ 'pcolor_log.py', 'pcolor_small.py', 'pie_demo2.py', - 'plotfile_demo.py', 'polar_demo.py', 'polar_legend.py', 'psd_demo.py', diff --git a/lib/matplotlib/pyplot.py b/lib/matplotlib/pyplot.py index 84cf4fc723cd..6d12da9b1c40 100644 --- a/lib/matplotlib/pyplot.py +++ b/lib/matplotlib/pyplot.py @@ -2176,6 +2176,7 @@ def polar(*args, **kwargs): return ret +@cbook.deprecated("3.1") def plotfile(fname, cols=(0,), plotfuncs=None, comments='#', skiprows=0, checkrows=5, delimiter=',', names=None, subplots=True, newfig=True, **kwargs):