Invalid WIDTH value, NumberFormatException when using WMS

[ocefpaf]

I am not sure if this is a cartopy bug or if I am doing something wrong. The code below fails to create an image with the error,

Invalid WIDTH value, NumberFormatException : For input string: "273.379119692"

I notice that, if I force the width and height to be integers, at slippy_image_artist.py line 55, the figure is created (but I am not sure if I mess up the proportions).

Other WebMapService URLs work fine with the width and height as float. Just some, like the one below, fails.

import cartopy.crs as ccrs
import matplotlib.pyplot as plt
from cartopy.mpl.gridliner import LONGITUDE_FORMATTER, LATITUDE_FORMATTER

from owslib.wms import WebMapService
url = "http://nowcoast.noaa.gov/wms/com.esri.wms.Esrimap/analyses"
wms = WebMapService(url)

subplot_kw = dict(projection=ccrs.PlateCarree())
fig, ax = plt.subplots(subplot_kw=subplot_kw)
ax.set_extent([-42, 0, -32, 0.5])
ax.add_wms(wms, 'NCEP_RAS_ANAL_RTG_SST')

gl = ax.gridlines(draw_labels=True)
gl.xlabels_top = gl.ylabels_right = False
gl.xformatter = LONGITUDE_FORMATTER
gl.yformatter = LATITUDE_FORMATTER

Thanks,

-Filipe

[rsignell-usgs]

It seems kind of crazy to request floating point pixels, so it would be nice if cartopy/owslib could round to nearest integer pixel, no?

[rsignell-usgs]

This was also asked (unanswered) here: https://groups.google.com/forum/#!searchin/scitools-iris/Filipe/scitools-iris/rpELfZtdDto/RVo7_kZkEyoJ

[ocefpaf]

Ultimately it boils down to the following URL being passed to OWSLib:

Bad URL (floats):

http://nowcoast.noaa.gov:80/wms/com.esri.wms.Esrimap/analyses?layers=NCEP_RAS_ANAL_RTG_SST&styles=&srs=EPSG%3A4326&format=image%2Fpng&request=GetMap&bgcolor=0xFFFFFF&height=392.0&width=480.0&version=1.1.1&bbox=-42.0%2C-33.790841270378365%2C0.0%2C0.5&exceptions=application%2Fvnd.ogc.se_xml&transparent=TRUE

Good URL (ints): http://nowcoast.noaa.gov:80/wms/com.esri.wms.Esrimap/analyses?layers=NCEP_RAS_ANAL_RTG_SST&styles=&srs=EPSG%3A4326&format=image%2Fpng&request=GetMap&bgcolor=0xFFFFFF&height=392&width=480&version=1.1.1&bbox=-42.0%2C-33.790841270378365%2C0.0%2C0.5&exceptions=application%2Fvnd.ogc.se_xml&transparent=TRUE

[pelson]

Closed by #587. Thanks for reporting @ocefpaf - this will be fixed by v0.12.0.

[ocefpaf]

Sorry, I should have been clearer :flushed:

np.ceil(2.1) results in 2.0, still not an int so the issue persists.

ServiceException: u'Invalid WIDTH value, NumberFormatException : For input string: "481.0"'

PS: Now that I know where to make the changes I can send a PR fixing this.