jcb.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Mon Oct  9 13:59:33 2017

@author: pianarol
"""

import numpy as np
import math


###function gss ###


def gss(t,s):
    '''JCB_GSS  - Linear Least Square fitting of Jacob solution

 Syntax: p = hp.jcb.gss(t,s,tmin,tmax)

   p(1) = a  = slope of Jacob straight line
   p(2) = t0 = intercept of the Jacob straight line

   t    = time 
   s    = drawdown
   tmin = optional argument: start of the fitting period
   tmax = optional argument: end   of the fitting period

 Description:
   First guess for the parameters of Jacob solution

 See also: jcb_dim, jcb_dmo, jcb_rpt'''

    tmin = t[0]
    tmax = t[len(t)-1]
    
    

    
    logt = []
    for i in range(0, len(t)):
        logt.append(math.log10(t[i]))
    t1 = []
    for i in range(0, len(logt)):
        t1.append(1)
    
    g = np.transpose([logt, t1])
    g1 = np.transpose(g)
    p1 = np.linalg.inv(np.dot(g1,g))
    p2 = np.dot(p1,g1)

    p = np.dot(p2,s)
    
    a = p[0]
    c = p[1]
    t0 = math.pow(10, -c/a)
    p[1] = t0
    
    return a,t0
    
###function dls ###


def dls(td):
    '''JCB_DLS - Jacob dimensionless drawdown

 Syntax: s,d = hp.jcb.dls(td)

 Description:
   provides the dimensionless drawdown and derivative at reduced time td

 See also: jcb_dmo
'''
    s = []
    
    for i in range(0, len(td)):
        s.append(0.5*(math.log(4*td[i])-0.5772))
    return s