package with python

1 files changed, 118 insertions, 0 deletions

diff --git a/metchart/skewt.py b/metchart/skewt.py
new file mode 100644
index 0000000..e674d09
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+++ b/metchart/skewt.py
@@ -0,0 +1,118 @@
+import matplotlib.gridspec as gridspec
+import matplotlib.pyplot as plt
+
+import numpy as np
+
+import metpy.calc as mpcalc
+from metpy.cbook import get_test_data
+from metpy.plots import add_metpy_logo, Hodograph, SkewT
+from metpy.units import units
+
+class Skewt:
+    def __init__(self, p, T, Td, max_barbs=20, title=None):
+        self._p = p
+        self._T = T
+        self._Td = Td
+
+        self._info_lines = []
+
+        self.barb_div = int(max(len(p)/max_barbs,1))
+
+
+        # Create a new figure. The dimensions here give a good aspect ratio
+        self._fig = plt.figure(figsize=(9, 9))
+        plt.rcParams["font.family"] = "monospace"
+        #self._fig = plt.figure()
+
+        if title is not None:
+            plt.suptitle(title, x=0, y=0, va='bottom', ha='left')
+
+        # Grid for plots
+        self._gs = gridspec.GridSpec(3, 3)
+        self._skew = SkewT(self._fig, rotation=45, subplot=self._gs[:, :2])
+
+        # Plot the data using normal plotting functions, in this case using
+        # log scaling in Y, as dictated by the typical meteorological plot
+        self._skew.plot(p, T, 'r')
+        self._skew.plot(p, Td, 'b')
+
+        plt.xlabel('$T$ $[^o C]$')
+        plt.ylabel('$p$ $[hPa]$')
+
+    def addWindUV(self, u, v):
+        self._u = u
+        self._v = v
+
+        ax = self._fig.add_subplot(self._gs[0, -1])
+        h = Hodograph(ax, component_range=max(u + v).magnitude)
+        h.add_grid(increment=20)
+        h.plot_colormapped(u, v, self._p)
+        plt.tight_layout()
+        plt.xlabel('$m/s$')
+        plt.ylabel('$m/s$')
+
+        self._skew.plot_barbs(self._p[::self.barb_div], u[::self.barb_div], v[::self.barb_div])
+
+    def addInfo(self, line):
+        self._info_lines.append(line)
+
+    def addAnalysis(self, analysis='ccl', shade=False):
+        f = {'ccl': self._cclAnalysis, 'lcl': self._lclAnalysis}
+
+        lvl, parcel = f[analysis]()
+
+        self._skew.plot(self._p, parcel, 'y')
+        self._skew.plot(lvl[0], lvl[1], 'o', markerfacecolor='red', linewidth=1)
+
+        # TODO why exception on cape_cin()?
+        # ValueError: zero-size array to reduction operation minimum which has no identity
+        # https://github.com/Unidata/MetPy/pull/3132
+        try:
+            cape, cin = mpcalc.cape_cin(self._p, self._T, self._Td, parcel, which_el='top')
+            self.addInfo(f'CAPE {int(cape.magnitude)} $J/kg$ CIN {int(cin.magnitude)} $J/kg$')
+        except ValueError:
+            print('CAPE/CIN Failed with ValueError')
+            self.addInfo('CAPE #### CIN ####')
+
+        if shade:
+            self._skew.shade_cape(self._p,self._T,parcel)
+            self._skew.shade_cin(self._p,self._T,parcel)
+
+    def _cclAnalysis(self):
+        #p = np.arange(max(self._p).magnitude, min(self._p).magnitude, -50) * units.hPa
+
+        ccl = mpcalc.ccl(self._p,self._T,self._Td)
+        ccl_ground=mpcalc.dry_lapse(self._p[:1], ccl[1], ccl[0])
+        ccl_ground_parcel= mpcalc.parcel_profile(self._p, ccl_ground[0], self._Td[0])
+
+        return (ccl, ccl_ground_parcel)
+
+    def _lclAnalysis(self):
+        ground_parcel= mpcalc.parcel_profile(self._p, self._T[0], self._Td[0])
+        lcl = mpcalc.lcl(self._p[0],self._T[0],self._Td[0])
+
+        return (lcl, ground_parcel)
+
+    def _buildInfoBox(self):
+        ax = self._fig.add_subplot(self._gs[1,-1])
+        ax.text(0, 0, '\n'.join(self._info_lines), ha='left', va='center',
+                size=10, fontfamily='monospace')
+        ax.axis("off")
+
+    def plot(self, filename=None):
+        self._buildInfoBox()
+
+        # Add the relevant special lines
+        #self._skew.ax.set_ylim(max(self._p), min(self._p))
+        self._skew.ax.set_ylim(1000, 100)
+        self._skew.plot_dry_adiabats(linewidth=1)
+        self._skew.plot_moist_adiabats(linewidth=1)
+        self._skew.plot_mixing_lines(linewidth=1)
+
+        # Good bounds for aspect ratio
+        self._skew.ax.set_xlim(-30, 40)
+
+        if filename is not None:
+            plt.savefig(filename)
+        else:
+            plt.show()