[Bug] .gif files don't loop

[TomNicholas]

.gif files created with animatplot only run once through, then stop on the final frame. They do loop properly when running interactively (in a Jupyter notebook) though.

I'm creating a gif in a jupyter notebook, using %matplotlib notebook. I save the gif, then try to open it using

![Ising](ising.gif "ising")

This displays the gif once through, then it stops on the final frame. If I rerun the cell then it just opens a static image of the final frame.

If I open the .gif file with another program it also stops on the final frame, so I think it's a problem with the created file.

I've tried explicitly passing repeat=True to FuncAnimation() inside animatplot.Animation, and I've also tried using the imagemagick writer rather than PillowWriter, but the problem persists.

A reproducible example, which is basically just this example):

%matplotlib notebook
import numpy as np
import matplotlib.pyplot as plt
import animatplot as amp

# Define LxL matrix
L = 55
# Initialize as random spin
M = 2*(np.random.rand(L,L)>.5)-1
J = 1
b = 2.5

nPer = 100

images = [M]
for i in range(100):
    M = M.copy()
    for dm in range(nPer):
        jj = int(np.random.rand()*L - 1)
        kk = int(np.random.rand()*L - 1)
        dE = 2*J*(M[jj+1,kk] + M[jj-1,kk] + M[jj,kk+1] + M[jj,kk-1])*M[jj,kk]
        if dE <= 0:
            M[jj,kk]*=-1
        else:
            if(np.random.rand()<np.exp(-b*dE)):
                M[jj,kk]*=-1
    images.append(M)
    M[:,-1] = M[:,0]
    M[-1,:] = M[0,:]

fig1, ax1 = plt.subplots()

block = amp.blocks.Imshow(images, axis=ax1)
anim = amp.Animation([block])

anim.controls()
anim.save_gif('ising')

![Ising](ising.gif "ising")

Also the output of using conda list to see which versions of everything I'm using:

# Name                    Version                   Build
alabaster                 0.7.12                   py36_0  
anaconda                  custom           py36hbbc8b67_0  
anaconda-client           1.7.2                    py36_0  
anaconda-project          0.8.2                    py36_0  
animatplot                0.4.0.dev1                <pip>
appdirs                   1.4.3            py36h28b3542_0  
asn1crypto                0.24.0                   py36_0  
astroid                   2.0.4                    py36_0  
astropy                   3.0.5            py36h7b6447c_0  
atomicwrites              1.2.1                    py36_0  
attrs                     18.2.0           py36h28b3542_0  
automat                   0.7.0                    py36_0  
babel                     2.6.0                    py36_0  
backcall                  0.1.0                    py36_0  
backports                 1.0                      py36_1  
backports.os              0.1.1                    py36_0  
backports.shutil_get_terminal_size 1.0.0                    py36_2  
beautifulsoup4            4.6.3                    py36_0  
bitarray                  0.8.3            py36h14c3975_0  
bkcharts                  0.2                      py36_0  
blas                      1.0                         mkl  
blaze                     0.11.3                   py36_0  
bleach                    3.0.2                    py36_0  
blosc                     1.14.4               hdbcaa40_0  
bokeh                     1.0.1                    py36_0  
boto                      2.49.0                   py36_0  
bottleneck                1.2.1            py36h035aef0_1  
bzip2                     1.0.6                h14c3975_5  
ca-certificates           2018.03.07                    0  
cairo                     1.14.12              h8948797_3  
certifi                   2018.10.15               py36_0  
cffi                      1.11.5           py36he75722e_1  
cftime                    1.0.2.1          py36hdd07704_0  
chardet                   3.0.4                    py36_1  
click                     7.0                      py36_0  
cloudpickle               0.6.1                    py36_0  
clyent                    1.2.2                    py36_1  
colorama                  0.4.0                    py36_0  
constantly                15.1.0           py36h28b3542_0  
contextlib2               0.5.5                    py36_0  
cryptography              2.3.1            py36hc365091_0  
curl                      7.61.0               h84994c4_0  
cycler                    0.10.0                   py36_0  
cython                    0.29             py36he6710b0_0  
cytoolz                   0.9.0.1          py36h14c3975_1  
dask                      0.20.2                   py36_0  
dask-core                 0.20.2                   py36_0  
datashape                 0.5.4                    py36_1  
dbus                      1.13.2               h714fa37_1  
decorator                 4.3.0                    py36_0  
defusedxml                0.5.0                    py36_1  
distributed               1.24.2                   py36_0  
docutils                  0.14                     py36_0  
entrypoints               0.2.3                    py36_2  
et_xmlfile                1.0.1                    py36_0  
expat                     2.2.6                he6710b0_0  
experi                    0.2.11                    <pip>
fastcache                 1.0.2            py36h14c3975_2  
filelock                  3.0.10                   py36_0  
flask                     1.0.2                    py36_1  
flask-cors                3.0.7                    py36_0  
fontconfig                2.13.0               h9420a91_0  
freetype                  2.9.1                h8a8886c_1  
fribidi                   1.0.5                h7b6447c_0  
get_terminal_size         1.0.0                haa9412d_0  
gevent                    1.3.7            py36h7b6447c_1  
glib                      2.56.2               hd408876_0  
glob2                     0.6                      py36_1  
gmp                       6.1.2                h6c8ec71_1  
gmpy2                     2.0.8            py36h10f8cd9_2  
graphite2                 1.3.12               h23475e2_2  
greenlet                  0.4.15           py36h7b6447c_0  
gst-plugins-base          1.14.0               hbbd80ab_1  
gstreamer                 1.14.0               hb453b48_1  
h5py                      2.8.0            py36h989c5e5_3  
harfbuzz                  1.8.8                hffaf4a1_0  
hdf4                      4.2.13               h3ca952b_2  
hdf5                      1.10.2               hba1933b_1  
heapdict                  1.0.0                    py36_2  
html5lib                  1.0.1                    py36_0  
hyperlink                 18.0.0                   py36_0  
icu                       58.2                 h9c2bf20_1  
idna                      2.7                      py36_0  
imageio                   2.4.1                    py36_0  
imagesize                 1.1.0                    py36_0  
importlib_metadata        0.6                      py36_0  
incremental               17.5.0                   py36_0  
intel-openmp              2019.1                      144  
ipykernel                 5.1.0            py36h39e3cac_0  
ipython                   7.1.1            py36h39e3cac_0  
ipython_genutils          0.2.0                    py36_0  
ipywidgets                7.4.2                    py36_0  
isort                     4.3.4                    py36_0  
itsdangerous              1.1.0                    py36_0  
jbig                      2.1                  hdba287a_0  
jdcal                     1.4                      py36_0  
jedi                      0.13.1                   py36_0  
jeepney                   0.4                      py36_0  
jinja2                    2.10                     py36_0  
jpeg                      9b                   h024ee3a_2  
jsonschema                2.6.0                    py36_0  
jupyter                   1.0.0                    py36_7  
jupyter_client            5.2.3                    py36_0  
jupyter_console           6.0.0                    py36_0  
jupyter_core              4.4.0                    py36_0  
jupyterlab                0.35.3                   py36_0  
jupyterlab_launcher       0.13.1                   py36_0  
jupyterlab_server         0.2.0                    py36_0  
keyring                   16.1.0                   py36_0  
kiwisolver                1.0.1            py36hf484d3e_0  
lazy-object-proxy         1.3.1            py36h14c3975_2  
libcurl                   7.61.0               h1ad7b7a_0  
libedit                   3.1.20170329         h6b74fdf_2  
libffi                    3.2.1                hd88cf55_4  
libgcc-ng                 8.2.0                hdf63c60_1  
libgfortran-ng            7.3.0                hdf63c60_0  
libnetcdf                 4.6.1                h10edf3e_1  
libpng                    1.6.35               hbc83047_0  
libsodium                 1.0.16               h1bed415_0  
libssh2                   1.8.0                h9cfc8f7_4  
libstdcxx-ng              8.2.0                hdf63c60_1  
libtiff                   4.0.9                he85c1e1_2  
libtool                   2.4.6                h7b6447c_5  
libuuid                   1.0.3                h1bed415_2  
libxcb                    1.13                 h1bed415_1  
libxml2                   2.9.8                h26e45fe_1  
libxslt                   1.1.32               h1312cb7_0  
llvmlite                  0.25.0           py36hd408876_0  
locket                    0.2.0                    py36_1  
lxml                      4.2.5            py36hefd8a0e_0  
lzo                       2.10                 h49e0be7_2  
markupsafe                1.1.0            py36h7b6447c_0  
matplotlib                3.0.1            py36h5429711_0  
mccabe                    0.6.1                    py36_1  
mistune                   0.8.4            py36h7b6447c_0  
mkl                       2018.0.3                      1  
mkl-service               1.1.2            py36h90e4bf4_5  
mkl_fft                   1.0.6            py36h7dd41cf_0  
mkl_random                1.0.1            py36h4414c95_1  
more-itertools            4.3.0                    py36_0  
mpc                       1.1.0                h10f8cd9_1  
mpfr                      4.0.1                hdf1c602_3  
mpmath                    1.0.0                    py36_2  
msgpack-python            0.5.6            py36h6bb024c_1  
multipledispatch          0.6.0                    py36_0  
natsort                   5.5.0                     <pip>
nbconvert                 5.3.1                    py36_0  
nbformat                  4.4.0                    py36_0  
ncurses                   6.1                  he6710b0_1  
netcdf4                   1.4.2            py36h4b4f87f_0  
networkx                  2.2                      py36_1  
nltk                      3.3.0                    py36_0  
nose                      1.3.7                    py36_2  
notebook                  5.7.2                    py36_0  
numba                     0.40.0           py36h962f231_0  
numexpr                   2.6.8            py36hd89afb7_0  
numpy                     1.15.4           py36h1d66e8a_0  
numpy-base                1.15.4           py36h81de0dd_0  
numpydoc                  0.8.0                    py36_0  
odo                       0.5.1                    py36_0  
olefile                   0.46                     py36_0  
openpyxl                  2.5.9                    py36_0  
openssl                   1.0.2p               h14c3975_0  
packaging                 18.0                     py36_0  
pandas                    0.23.4           py36h04863e7_0  
pandoc                    2.2.3.2                       0  
pandocfilters             1.4.2                    py36_1  
pango                     1.42.4               h049681c_0  
parso                     0.3.1                    py36_0  
partd                     0.3.9                    py36_0  
patchelf                  0.9                  he6710b0_3  
path.py                   11.5.0                   py36_0  
pathlib2                  2.3.2                    py36_0  
patsy                     0.5.1                    py36_0  
pcre                      8.42                 h439df22_0  
pep8                      1.7.1                    py36_0  
pexpect                   4.6.0                    py36_0  
pickleshare               0.7.5                    py36_0  
pillow                    5.3.0            py36h34e0f95_0  
pip                       18.1                     py36_0  
pixman                    0.34.0               hceecf20_3  
pkginfo                   1.4.2                    py36_1  
pluggy                    0.8.0                    py36_0  
ply                       3.11                     py36_0  
prometheus_client         0.4.2                    py36_0  
prompt_toolkit            2.0.7                    py36_0  
psutil                    5.4.8            py36h7b6447c_0  
ptyprocess                0.6.0                    py36_0  
py                        1.7.0                    py36_0  
pyasn1                    0.4.4            py36h28b3542_0  
pyasn1-modules            0.2.2                    py36_0  
pycodestyle               2.4.0                    py36_0  
pycosat                   0.6.3            py36h14c3975_0  
pycparser                 2.19                     py36_0  
pycrypto                  2.6.1            py36h14c3975_9  
pycurl                    7.43.0.2         py36hb7f436b_0  
pyflakes                  2.0.0                    py36_0  
pygments                  2.2.0                    py36_0  
pyhamcrest                1.9.0                    py36_2  
pylint                    2.1.1                    py36_0  
pyodbc                    4.0.24           py36he6710b0_0  
pyopenssl                 18.0.0                   py36_0  
pyparsing                 2.3.0                    py36_0  
pyqt                      5.9.2            py36h05f1152_2  
pysocks                   1.6.8                    py36_0  
pytables                  3.4.4            py36ha205bf6_0  
pytest                    4.0.0                    py36_0  
pytest-arraydiff          0.2              py36h39e3cac_0  
pytest-astropy            0.4.0                    py36_0  
pytest-doctestplus        0.2.0                    py36_0  
pytest-openfiles          0.3.0                    py36_0  
pytest-remotedata         0.3.1                    py36_0  
python                    3.6.6                h6e4f718_2  
python-dateutil           2.7.5                    py36_0  
pytz                      2018.7                   py36_0  
pywavelets                1.0.1            py36hdd07704_0  
pyyaml                    3.13             py36h14c3975_0  
pyzmq                     17.1.2           py36h14c3975_0  
qt                        5.9.6                h8703b6f_2  
qtawesome                 0.5.3                    py36_0  
qtconsole                 4.4.2                    py36_0  
qtpy                      1.5.2                    py36_0  
readline                  7.0                  h7b6447c_5  
requests                  2.20.1                   py36_0  
rope                      0.11.0                   py36_0  
ruamel_yaml               0.15.46          py36h14c3975_0  
scikit-image              0.14.0           py36hf484d3e_1  
scikit-learn              0.20.1           py36h4989274_0  
scipy                     1.1.0            py36hfa4b5c9_1  
seaborn                   0.9.0                    py36_0  
secretstorage             3.1.0                    py36_0  
send2trash                1.5.0                    py36_0  
service_identity          17.0.0           py36h28b3542_0  
setuptools                40.6.2                   py36_0  
simplegeneric             0.8.1                    py36_2  
singledispatch            3.4.0.3                  py36_0  
sip                       4.19.8           py36hf484d3e_0  
six                       1.11.0                   py36_1  
snappy                    1.1.7                hbae5bb6_3  
snowballstemmer           1.2.1                    py36_0  
sortedcollections         1.0.1                    py36_0  
sortedcontainers          2.0.5                    py36_0  
sphinx                    1.8.2                    py36_0  
sphinxcontrib             1.0                      py36_1  
sphinxcontrib-websupport  1.1.0                    py36_1  
spyder                    3.3.2                    py36_0  
spyder-kernels            0.3.0                    py36_0  
sqlalchemy                1.2.14           py36h7b6447c_0  
sqlite                    3.25.3               h7b6447c_0  
statsmodels               0.9.0            py36h035aef0_0  
sympy                     1.3                      py36_0  
tblib                     1.3.2                    py36_0  
terminado                 0.8.1                    py36_1  
testpath                  0.4.2                    py36_0  
tk                        8.6.8                hbc83047_0  
toolz                     0.9.0                    py36_0  
tornado                   5.1.1            py36h7b6447c_0  
tqdm                      4.28.1           py36h28b3542_0  
traitlets                 4.3.2                    py36_0  
twisted                   18.9.0           py36h7b6447c_0  
typed-ast                 1.1.0            py36h14c3975_0  
unicodecsv                0.14.1                   py36_0  
unixodbc                  2.3.7                h14c3975_0  
urllib3                   1.23                     py36_0  
wcwidth                   0.1.7                    py36_0  
webencodings              0.5.1                    py36_1  
werkzeug                  0.14.1                   py36_0  
wheel                     0.32.3                   py36_0  
widgetsnbextension        3.4.2                    py36_0  
wrapt                     1.10.11          py36h14c3975_2  
wurlitzer                 1.0.2                    py36_0  
xarray                    0.10.9+50.g17815b4           <pip>
xBOUT                     0.1                       <pip>
xcollect                  0.1                       <pip>
xlrd                      1.1.0                    py36_1  
xlsxwriter                1.1.2                    py36_0  
xlwt                      1.3.0                    py36_0  
xstorm                    0.1                       <pip>
xz                        5.2.4                h14c3975_4  
yaml                      0.1.7                had09818_2  
zeromq                    4.2.5                hf484d3e_1  
zict                      0.1.3                    py36_0  
zlib                      1.2.11               h7b6447c_3  
zope                      1.0                      py36_1  
zope.interface            4.6.0            py36h7b6447c_0

[t-makaro]

This is actually a bug with matplotlib's pillowWriter. See matplotlib/matplotlib#11787. I submitted a bug fix and it will be released with matplotlib 3.1. I actually monkey patched the fix into my local version of matplotlib, so that when I made the documentation the gif's looped.

You can use anim.save('image.gif', writer='imagemagick') as a work around for now. If imagemagick isn't making looping gifs, then matplotlib may not be finding imagemagick and defaulting back to PillowWriter. See matplotlib/matplotlib#11792

[TomNicholas]

Changing to imagemagick with that command worked, thanks!

[educhana]

As a workaround using Pillow, you can subclass PillowWriter:

from matplotlib.animation import PillowWriter    

class LoopingPillowWriter(PillowWriter):
    def finish(self):
        self._frames[0].save(
            self._outfile, save_all=True, append_images=self._frames[1:],
            duration=int(1000 / self.fps), loop=0)

ani = ArtistAnimation(fig, images)
ani.save('data.gif', writer=LoopingPillowWriter(fps=15))    

[jonnyhtw]

Just to note that I am having this error too and look forward to a fix from the matplotlib folks.

Loving this software though!

Cheers

[jonnyhtw]

... Just a quick note to say that a quick workaround is to save the gif and then run this at the terminal...

> convert -loop 0 mygif.gif mygif.gif

Works for me!