PhD_UH

by Zhanliang

THESE CODES MAINLY USE FOR CALCULATE UNIT HYDROGRAPH

Hydrographs

From NEH Hydrology Ch. 16, Ex. 16-1:

Unit Hydrograph

The theory can be found in THIS LINK

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My Code

hydrograpg.py

This py code is a class, which contains methods about calculate varialbes of UH and plot the results. Necessary packages:

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.pylab import rcParams

• Method calc() to calculate:

    def calc(self):
        #Tp represents the Tl in Chapter11, means basin lag time
#        self.tp = self.C1 * self.Ct * \
#                  ((self.L * 0.621371) * (self.Lc * 0.621371) ** 0.3)
        self.tp = self.C1 * self.Ct * \
                  ((self.L * self.Lc) ** 0.3)
        self.tr = self.tp / 5.5
        # tpr is basin lag, same as tlr in Chapter 11
#        self.tPR = self.tp + 0.25 * (self.tR - self.tr)
        self.tPR = self.tp + 0.25 * (self.tR - self.tr)
        # qpr is the peak discharge per unit of watershed area
        self.QPR = 2.75 * self.Cp * (self.A / self.tPR)
        # width of the UH at values of 50% with a 2.14 values of Cw
        self.W50 = 2.14 / ((self.QPR / self.A) ** 1.08)
        # width of the UH at values of 75% with a 1.22 values of Cw
        self.W75 = 1.22 / ((self.QPR / self.A) ** 1.08)
        # tb means the base time
        self.Tb = 11.11 * (self.A / self.QPR) - 1.5 * self.W50 - self.W75
        return dict(tp=self.tp, tr=self.tr, tPR=self.tPR, QPR=self.QPR,
                    W50=self.W50, W75=self.W75, Tb=self.Tb, tR=self.tR)

• Method plot() to plot

    def plot(self):
        self.calc()
        self.plot_t = np.array([0, (self.tr / 2 + self.tPR) - self.W50 / 3,
                               (self.tr / 2 + self.tPR) - self.W75 / 3,
                               self.tr / 2 + self.tPR,
                               (self.tr / 2 + self.tPR) + self.W75 / 3,
                               (self.tr / 2 + self.tPR) + self.W50 / 3,
                               self.Tb]
                               )
        self.plot_Q = np.array([0, self.QPR * 0.5, self.QPR * 0.75,
                               self.QPR, self.QPR * 0.75, self.QPR * 0.5, 0])
        fig, ax1 = plt.subplots(1, 1)
        ax1.plot(self.plot_t, self.plot_Q)
        plt.vlines(self.plot_t[3], self.plot_Q[3], 0,
                   color='DarkOrange', linestyle='dashed', lw=2)
        plt.text(self.plot_t[3], self.plot_Q[3], 'QPR')
        plt.hlines(self.plot_Q[2], self.plot_t[2], self.plot_t[4],
                   color='DarkOrange', linestyle='dashed', lw=2)
        plt.text(self.plot_t[4] + 0.3, self.plot_Q[2], 'W75')
        plt.hlines(self.plot_Q[1], self.plot_t[1], self.plot_t[5],
                   color='DarkOrange', linestyle='dashed', lw=2)
        plt.text(self.plot_t[5] + 0.3, self.plot_Q[1], 'W50')
        plt.hlines(self.QPR + 0.5, 0, self.tr,
                   color='Blue', lw=15)
        plt.hlines(self.QPR + 0.5, self.tr / 2, self.plot_t[3],
                   color='DarkOrange', linestyle='-.', lw=2.5)
        plt.text(0.5, self.QPR, 'tR  ' + str(round(self.tr, 4)) + '  hr')
        plt.text(self.Tb / 2, 0.5,
                 'Base time: ' + str(round(self.Tb, 4)) + ' hr')
        plt.hlines(0, 0, self.Tb,
                   color='DarkOrange', linestyle='dashed', lw=5)
        plt.title('Snyder Synthetic Unit Hydrograph')
        plt.xlabel('t (hr)')
        plt.ylabel('Q m3/sec')
        plt.grid()
        plt.savefig('SUH_{}_{}_tr.png'.format(self.name,self.tR),
                    bbox_inches='tight')

example_UH_Mykonos.py

This is the main(), and if you want to use it, u need to input some varialbes of target catchment. try to run it to get nice pics.

A = 2.7
L = 2.10
Lc = 1.37
C1 = 1
Ct = 1.9
Cp = 0.65
tR = 0.25

#Make ShyderUH
mykonosUH = SnyderUH(name, A, L, Lc, C1, Ct, Cp, tR)

# Calculate ShyderUh
print(mykonosUH.calc())

# View plot
mykonosUH.plot()

# Calculate UH & View plot for various rainfall durations
for item in [0.25,0.5,1,2,3,4]:
	UH = SnyderUH(name, A, L, Lc, C1, Ct, Cp, item)
	UH.calc()
	UH.plot()                                                              
	print("tR: {} hr, Q: {}, Tb:{} hr".format(UH.tR, UH.QPR, UH.Tb))

This part contains two codes, and the reference is in Here, which was originally written by Anastasiadis Stavros. Copyright (C) 2014 University of Aegean, Research Program ISLA!

1.unitHydrograph.m

This .m file is a script based on Matlab for obtain Unit Hydrograph. See the whole file and try run it.

2.Nakayasu_UH.m

This .m file is a script based on Matlab for obtain Unit Hydrograph using Nakayasu method.

3. Test.py

This .py file is a script about LSTM networks. It mainlu uses these modules:

import numpy as np
import torch
from torch import nn
import matplotlib.pyplot as plt

Download and run it, you will get a nice train img!

To be continue...