René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Speed up Basemap / Pickling?","articleBody":"[Original report at SourceForge, opened Mon Jun 12 02:49:17 2006](https://sourceforge.net/tracker/?func=detail\u0026aid=1504590\u0026group_id=80706\u0026atid=560721)\n\nThanks in advance for taking the time to reply to \nthis request.\n\nI am using the Basemap package of matplotlib to \ngenerate plots upon request from a website. The \nwebsite interface generates a datafile to be loaded \nand ploted on top a global coastline map. Typically, \nthe following line of code takes about 4.5 seconds:\n\n map = Basemap(projection='cyl',resolution='c')\n map.fillcontinents ...\n\nHaving resorted to the crude resolution level, there \nappears to be little else that can be done to \nexpedite this line of code.\n\nOne thought was to pickle the object and recover the \npicked map object, although this was rather \nunsuccessful:\n\n from matplotlib.figure import Figure\n from matplotlib.backends.backend_agg import \nFigureCanvasAgg as FigureCanvas\n\n fig = Figure()\n canvas = FigureCanvas(fig)\n ax = fig.add_axes([0.125,0.175,0.75,0.75])\n pickle_file = open(pickle_path+\"/glm.map.obj\",'r')\n map = pickle.load(pickle_file)\n pickle_file.close()\n map.set_axes_limits(ax=ax) \n fig.set_figsize_inches((8,map.aspect*8.))\n map.fillcontinents ...\n\nThis not only resulted in map being diassociated with \nthe figure axis (since the Basemap could not be \npickled after calling it with the ax=ax parameter) \nbut the pickle.load command took over 7 seconds \n(worse than simply generating the plot from scratch \nevery time).\n\nIs there a way to store the map object into a file \nand plot the data on top of the loaded map object \neach time the python script executes rather than \nregenerating the Basemap each time and wasting 4.5 \nseconds?\n\nAlternatively, perhaps there is a method I am not \naware of for writing a png or svg file and then \nreloading the image and ploting on top of it to avoid \npickling?\n\nThanks again for the help.\n\nRupert Minnett\nUCSD - SIO\nIGPP - Scripps Institute of Oceanography\n","author":{"url":"https://github.com/ddale","@type":"Person","name":"ddale"},"datePublished":"2011-06-20T21:18:52.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/265/matplotlib/issues/265"}