### Plotting state boundary data from shapefiles using Python

The great folks at census.gov have put up some of the data they collect so we can download and use it. On this page they have data relating to state boundaries. The files are available as zipped directories containing a shapefile and other metadata information. If you want to plot state boundaries and some state metadata (like zip code, state name) the .shp shapefile is sufficient. Assuming that the shape file is `'tl_2010_us_state10/tl_2010_us_state10.shp'`, some sample code using the pyshp package is:
```#http://stackoverflow.com/questions/10871085/viewing-a-polygon-read-from-shapefile-with-matplotlib
#http://stackoverflow.com/questions/1441717/plotting-color-map-with-zip-codes-in-r-or-python
import shapefile as sf, pylab

state_shapes = map_f.shapes()

pylab.plot([px[0] if px[0] <0 else px[0]-360 for px in state_shapes[n].points],[px[1] for px in state_shapes[n].points],'k.',ms=2)

pylab.axis('scaled')
```
The pyshp package makes things so easy! Note that you can plot continuous lines instead of dots for the state boundaries, however, for some states like Alaska and Florida with islands, where the boundaries are not contiguous, you get nasty disjoint lines. Removing this requires much more processing (unless you do it by hand and break down states into "sub-states".

### Python: Multiprocessing: passing multiple arguments to a function

Write a wrapper function to unpack the arguments before calling the real function. Lambda won't work, for some strange un-Pythonic reason.

import multiprocessing as mp def myfun(a,b): print a + b def mf_wrap(args): return myfun(*args) p = mp.Pool(4) fl = [(a,b) for a in range(3) for b in range(2)] #mf_wrap = lambda args: myfun(*args) -> this sucker, though more pythonic and compact, won't work p.map(mf_wrap, fl)

### Flowing text in inkscape (Poster making)

You can flow text into arbitrary shapes in inkscape. (From a hint here).

You simply create a text box, type your text into it, create a frame with some drawing tool, select both the text box and the frame (click and shift) and then go to text->flow into frame.

UPDATE:

Trying to enter sentence so that text forms the number three...any ideas?
The solution:
Type '3' using the text toolConvert to path using object->pathSize as necessaryRemove fillUngroupType in actual text in new text boxSelect the text and the '3' pathFlow the text

### Drawing circles using matplotlib

Use the pylab.Circle command

import pylab #Imports matplotlib and a host of other useful modules cir1 = pylab.Circle((0,0), radius=0.75, fc='y') #Creates a patch that looks like a circle (fc= face color) cir2 = pylab.Circle((.5,.5), radius=0.25, alpha =.2, fc='b') #Repeat (alpha=.2 means make it very translucent) ax = pylab.axes(aspect=1) #Creates empty axes (aspect=1 means scale things so that circles look like circles) ax.add_patch(cir1) #Grab the current axes, add the patch to it ax.add_patch(cir2) #Repeat pylab.show()