94.2, 92.5, 90.8, 89.1, 87.5, 85.9, 84.3, 81.2, 78.2, 75.3, 72.4, 69.7,
57.2, 46.6, 37.6, 30.1, 23.8, 18.7, 14.5, 11.1
],
dtype=double)
DS = DataSet(alt_mArr,
PaArr,
xName='altitude',
yName='pressure',
xUnits='m',
yUnits='Pa')
guessD = {'A': 101325, 'c': 1, 'd': 2.25577E-5, 'n': 5.25588}
print('guessD Before', guessD)
CFit_toterr = NonLinCurveFit(DS,
rhs_eqnStr='A*(c - d*x)**n',
constDinp=guessD,
fit_best_pcent=0) # 0=fit best total error
print('guessD After', guessD)
print('=' * 55)
print('..........Total Error............')
print(CFit_toterr.get_full_description())
print('=' * 55)
print('..........Percent Error............')
CFit_pcterr = NonLinCurveFit(DS,
rhs_eqnStr='A*(c - d*x)**n',
constDinp=guessD,
fit_best_pcent=1) # 1=fit best percent error
print(CFit_pcterr.get_full_description())
print('=' * 55)
from matplotlib import pyplot as plt
got_plt = True
except:
got_plt = False
from numpy import array
from xymath.dataset import DataSet
from xymath.nonlinfit import NonLinCurveFit
xdata = array([-2,-1.64,-1.33,-0.7,0,0.45,1.2,1.64,2.32,2.9])
ydata = array([0.699369,0.700462,0.695354,1.03905,1.97389,2.41143,
1.91091,0.919576,-0.730975,-1.42001])
DS = DataSet(xdata, ydata, xName='x', yName='y')
guessD = {'p1':1.0, 'p2':0.2}
CFit = NonLinCurveFit(DS, rhs_eqnStr='p1*cos(p2*x) + p2*sin(p1*x)',
constDinp=guessD, fit_best_pcent=0) # 0=fit best total error
print( 'residuals from XYmath = %g'%sum( (CFit.eval_xrange( xdata ) - ydata)**2 ) )
print( 'residuals from author = 0.053812696547933969' )
print('')
print(CFit.get_full_description())
if got_plt:
plt.plot( xdata, ydata, 'o', markersize=10 )
xPlotArr, yPlotArr = CFit.get_xy_plot_arrays( Npoints=100, logScale=False)
plt.plot( xPlotArr, yPlotArr )
plt.title('Trig Function: p1*cos(p2*x) + p2*sin(p1*x)')
plt.show()
30.1,
23.8,
18.7,
14.5,
11.1,
],
dtype=double,
)
DS = DataSet(alt_mArr, PaArr, xName="altitude", yName="pressure", xUnits="m", yUnits="Pa")
guessD = {"A": 101325, "c": 1, "d": 2.25577e-5, "n": 5.25588}
print("guessD Before", guessD)
CFit_toterr = NonLinCurveFit(
DS, rhs_eqnStr="A*(c - d*x)**n", constDinp=guessD, fit_best_pcent=0
) # 0=fit best total error
print("guessD After", guessD)
print("=" * 55)
print("..........Total Error............")
print(CFit_toterr.get_full_description())
print("=" * 55)
print("..........Percent Error............")
CFit_pcterr = NonLinCurveFit(
DS, rhs_eqnStr="A*(c - d*x)**n", constDinp=guessD, fit_best_pcent=1
) # 1=fit best percent error
print(CFit_pcterr.get_full_description())
print("=" * 55)
# To set parameters to reference values from www.engineeringtoolbox.com do this:
def test_should_always_pass_cleanly(self):
"""Should always pass cleanly."""
nlf = NonLinCurveFit(self.myds,
rhs_eqnStr='A*sin(2*pi*k*x+theta)',
fit_best_pcent=1,
constDinp=None)
