Pcolormesh with Negative Coordinates and Values
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| 2.0                                                                            |
| *++*****###%%%%%########+++++=======++++++#######%%%%%###*****++++++++++++++++ |
| +++*****###%%%%%########+++++=======++++++#######%%%%%###*****++++++++++++++++ |
| 1.5+++**###%%%%%#####+++==-------------===++#####%%%%%###***+++++============= |
| ===+++**###%%%%%#####===-----:::::::------==#####%%%%%###***++===------------- |
| *==+++++***%%########===--:::::::::::::---==########%%***+++++===------------- |
| *==+++**###%%%%%#####===-----:::::::------==#####%%%%%###***++=====--------=== |
| 1.0+++**###%%%%%#####+++=====-------======++#####%%%%%###***+++++============= |
| ******#####%%%%%##***########+++++++########***##%%%%%######*****+++++++++++++ |
| ########%%%%%%%%%%#############################%%%%%%%%%%##################### |
| *%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
| 0.5########%%%%%%%########*************########%%%%%%%######################## |
| +++########%%%%%##******++++++++++++++++++*****##%%%%%########+++++========+++ |
| *==+++#####%%%%%##***+++++=============+++++***##%%%%%######++===------------- |
| *--===#####%%%%%##***+++==-------------===++***##%%%%%######==-----::::::::--- |
| 0.0===#######%%%**++++++==-------------===+++++**%%%########==---::::::::::::: |
| *--===#####%%%%%##***+++=====-------======++***##%%%%%######==-----::::::::--- |
| ===+++#####%%%%%##***+++++=============+++++***##%%%%%######++=====--------=== |
| *#####**###%%%%%#####*****+++++++++++++*****#####%%%%%###***#######++++++++### |
| -0.5####%%%%%%%%%%#############################%%%%%%%%%%##################### |
| %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
| *#######%%%%%%%%#################################%%%%%%%%########************* |
| *####*##%%%*%%%%#*#####*#####*#####*#####*#####*#%%%%*%%%##*#####************* |
|-2.0        -1.5          -1.0         -0.5         0.0           0.5       1.0 |
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