online_gumbel2:   Flood frequency by the Gumbel method 2 (extended to 10000 yr)

Formulas

1/T = 1 - e-e-y                y = - ln {ln [T/(T-1)]}

x = xave + Ks                y = yn,ave + Kσn

Reference

Ponce, V. M., 1989. Engineering Hydrology, Principles and Practices,
Prentice Hall, pages 223-226.
INPUT DATA:
Stream (optional):  

Select:   

[Choose SI (metric) or U.S. Customary units].

[Sample input file]   [Sample output file] 

[Note that the method can also be used with precipitation data (cm, mm, or in); in this case, output units is equal to input units].

Enter length of flood series (number of years):     

Enter flood series Q (m3 s-1 ) [ft3 s-1] (separate each value with a comma; maximum string length is 720 characters):     

ECHO OF INPUT:

Stream:  

n =  

Q(1) =  .   

OUTPUT:

iReturn period T
(yr)		Probability P
(percent)		Gumbel variate yFlood discharge Q
(m3/s)
00000

             

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