Basemap/ orthographic projection plot doesn't respect globe boundary

Picking up on an old thread. Hopefully Jeff is still listening in...

···

On 2010-04-04 23:24, Jeff Whitaker wrote:

On 4/4/10 11:06 AM, Will Hewson wrote:

Hi again Jeff et al...

I've had a play around with the extra few lines of code - on paper this
seems like it should solve the problems I'm experiencing. However, an
error's being thrown up by the transform scalar function, as my lons and
lats won't necessarily be increasing. The data I'm plotting is satellite
data and so at the beginning and end of the orbit file lats go over the pole
from 90 to -90, with a similar problem for the lons - whereby the data is
taken across the satellite track. I've thought about sorting the data before
passing it to transform_scalar but I'm always going to be left with the
problem in either lats or lons.

I've uploaded the file I'm currently working with this time. It's three
columns of lons, lats and z values.

Once again, many thanks for your help.

Will.

http://old.nabble.com/file/p28133659/test.plt test.plt

Will: Is it a regular lat/lon grid or a satellite swath? If it's the
latter, you can't use my solution.

-Jeff

What if it _is_ a satellite swath? Can I get around the problem of
off-projection plotting with Basemap.pcolormesh()?
Example code and plots can be found at
http://pythonbits.blogspot.com/2011/09/i-have-problem-with-basemap-plotting.html

Thanks,
Jakob Malm

Jakob: I think that's the price you pay for the speed of pcolormesh (vs pcolor). It appears to make more assumptions about the structure of your data. I don't see any way around it.

-Jeff

···

On 9/8/11 1:51 AM, Jakob Malm wrote:

Picking up on an old thread. Hopefully Jeff is still listening in...

On 2010-04-04 23:24, Jeff Whitaker wrote:

On 4/4/10 11:06 AM, Will Hewson wrote:

Hi again Jeff et al...

I've had a play around with the extra few lines of code - on paper this
seems like it should solve the problems I'm experiencing. However, an
error's being thrown up by the transform scalar function, as my lons and
lats won't necessarily be increasing. The data I'm plotting is satellite
data and so at the beginning and end of the orbit file lats go over the pole
from 90 to -90, with a similar problem for the lons - whereby the data is
taken across the satellite track. I've thought about sorting the data before
passing it to transform_scalar but I'm always going to be left with the
problem in either lats or lons.

I've uploaded the file I'm currently working with this time. It's three
columns of lons, lats and z values.

Once again, many thanks for your help.

Will.

http://old.nabble.com/file/p28133659/test.plt test.plt

Will: Is it a regular lat/lon grid or a satellite swath? If it's the
latter, you can't use my solution.

-Jeff

What if it _is_ a satellite swath? Can I get around the problem of
off-projection plotting with Basemap.pcolormesh()?
Example code and plots can be found at
http://pythonbits.blogspot.com/2011/09/i-have-problem-with-basemap-plotting.html

Thanks,
Jakob Malm

2011/9/8 Jeff Whitaker <jswhit@...146...>:

···

On 9/8/11 1:51 AM, Jakob Malm wrote:

Picking up on an old thread. Hopefully Jeff is still listening in...

On 2010-04-04 23:24, Jeff Whitaker wrote:

On 4/4/10 11:06 AM, Will Hewson wrote:

Hi again Jeff et al...

I've had a play around with the extra few lines of code - on paper this
seems like it should solve the problems I'm experiencing. However, an
error's being thrown up by the transform scalar function, as my lons and
lats won't necessarily be increasing. The data I'm plotting is satellite
data and so at the beginning and end of the orbit file lats go over the
pole
from 90 to -90, with a similar problem for the lons - whereby the data
is
taken across the satellite track. I've thought about sorting the data
before
passing it to transform_scalar but I'm always going to be left with the
problem in either lats or lons.

I've uploaded the file I'm currently working with this time. It's three
columns of lons, lats and z values.

Once again, many thanks for your help.

Will.

http://old.nabble.com/file/p28133659/test.plt test.plt

Will: Is it a regular lat/lon grid or a satellite swath? If it's the
latter, you can't use my solution.

-Jeff

What if it _is_ a satellite swath? Can I get around the problem of
off-projection plotting with Basemap.pcolormesh()?
Example code and plots can be found at

http://pythonbits.blogspot.com/2011/09/i-have-problem-with-basemap-plotting.html

Thanks,
Jakob Malm

Jakob: I think that's the price you pay for the speed of pcolormesh (vs
pcolor). It appears to make more assumptions about the structure of your
data. I don't see any way around it.

-Jeff

Hmm... I believe I have been able to get around it previously, but
perhaps I just fell back to using pcolor...

Thanks,
Jakob