[Python] 2d density contour plot with matplotlib

I'm attempting to plot my dataset, x and y (generated from a csv file via numpy.genfromtxt('/Users/.../somedata.csv', delimiter=',', unpack=True)) as a simple density plot. To ensure this is self containing I will define them here:

x = [ 0.2933215 0.2336305 0.2898058 0.2563835 0.1539951 0.1790058
0.1957057 0.5048573 0.3302402 0.2896122 0.4154893 0.4948401
0.4688092 0.4404935 0.2901995 0.3793949 0.6343423 0.6786809
0.5126349 0.4326627 0.2318232 0.538646 0.1351541 0.2044524
0.3063099 0.2760263 0.1577156 0.2980986 0.2507897 0.1445099
0.2279241 0.4229934 0.1657194 0.321832 0.2290785 0.2676585
0.2478505 0.3810182 0.2535708 0.157562 0.1618909 0.2194217
0.1888698 0.2614876 0.1894155 0.4802076 0.1059326 0.3837571
0.3609228 0.2827142 0.2705508 0.6498625 0.2392224 0.1541462
0.4540277 0.1624592 0.160438 0.109423 0.146836 0.4896905
0.2052707 0.2668798 0.2506224 0.5041728 0.201774 0.14907
0.21835 0.1609169 0.1609169 0.205676 0.4500787 0.2504743
0.1906289 0.3447547 0.1223678 0.112275 0.2269951 0.1616036
0.1532181 0.1940938 0.1457424 0.1094261 0.1636615 0.1622345
0.705272 0.3158471 0.1416916 0.1290324 0.3139713 0.2422002
0.1593835 0.08493619 0.08358301 0.09691083 0.2580497 0.1805554 ]

y = [ 1.395807 1.31553 1.333902 1.253527 1.292779 1.10401 1.42933
1.525589 1.274508 1.16183 1.403394 1.588711 1.346775 1.606438
1.296017 1.767366 1.460237 1.401834 1.172348 1.341594 1.3845
1.479691 1.484053 1.468544 1.405156 1.653604 1.648146 1.417261
1.311939 1.200763 1.647532 1.610222 1.355913 1.538724 1.319192
1.265142 1.494068 1.268721 1.411822 1.580606 1.622305 1.40986
1.529142 1.33644 1.37585 1.589704 1.563133 1.753167 1.382264
1.771445 1.425574 1.374936 1.147079 1.626975 1.351203 1.356176
1.534271 1.405485 1.266821 1.647927 1.28254 1.529214 1.586097
1.357731 1.530607 1.307063 1.432288 1.525117 1.525117 1.510123
1.653006 1.37388 1.247077 1.752948 1.396821 1.578571 1.546904
1.483029 1.441626 1.750374 1.498266 1.571477 1.659957 1.640285
1.599326 1.743292 1.225557 1.664379 1.787492 1.364079 1.53362
1.294213 1.831521 1.19443 1.726312 1.84324 ]


Now, I have used many attempts to plot my contours using variations on:

delta = 0.025
OII_OIII_sAGN_sorted = numpy.arange(numpy.min(OII_OIII_sAGN), numpy.max(OII_OIII_sAGN), delta)
Dn4000_sAGN_sorted = numpy.arange(numpy.min(Dn4000_sAGN), numpy.max(Dn4000_sAGN), delta)
OII_OIII_sAGN_X, Dn4000_sAGN_Y = np.meshgrid(OII_OIII_sAGN_sorted, Dn4000_sAGN_sorted)

Z1 = matplotlib.mlab.bivariate_normal(OII_OIII_sAGN_X, Dn4000_sAGN_Y, 1.0, 1.0, 0.0, 0.0)
Z2 = matplotlib.mlab.bivariate_normal(OII_OIII_sAGN_X, Dn4000_sAGN_Y, 0.5, 1.5, 1, 1)
# difference of Gaussians
Z = 0.2 * (Z2 - Z1)
pyplot_middle.contour(OII_OIII_sAGN_X, Dn4000_sAGN_Y, Z, 12, colors='k')


This doesn't seem to give the desired output.I have also tried:

H, xedges, yedges = np.histogram2d(OII_OIII_sAGN,Dn4000_sAGN)
extent = [xedges[0],xedges[-1],yedges[0],yedges[-1]]
ax.contour(H, extent=extent)


Not quite working as I wanted either. Essentially, I am looking for something similar to this:



If anyone could help me with this I would be very grateful, either by suggesting a totally new method or modifying my existing code. Please also attach images of your output if you have some useful techniques or ideas.

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