onlineregression15:   Hyperbolic regression (intensity-duration regression)    ⇒   i = f(tr-1)

Formulas

1/i = (tr/a) + (b/a)              y = α + βx

α = b/a        x = tr        β = 1/a        y = 1/i

β = [Σ(xy)-(ΣxΣy)/n]/{Σ(x2)-[(Σx)2/n]}

α = [Σy-(βΣx)]/n

Reference

Ponce, V. M. 1989. Engineering Hydrology, Principles and Practices. Prentice Hall, pages 246-248.
Example
INPUT DATA:

Enter array size n:     

Enter paired values of arrays i and tr (separate each value with a comma; maximum string length is 300 characters).

i:      

tr:     

ECHO OF INPUT:


Warning: Undefined variable $number in /var/www/html/ponce/onlineregression15.php on line 208
n =  


Warning: Undefined variable $number in /var/www/html/ponce/onlineregression15.php on line 210

Warning: Undefined variable $j in /var/www/html/ponce/onlineregression15.php on line 216

Warning: Undefined variable $invar in /var/www/html/ponce/onlineregression15.php on line 217

Warning: Trying to access array offset on null in /var/www/html/ponce/onlineregression15.php on line 217
i(1) =  .   


Warning: Undefined variable $number in /var/www/html/ponce/onlineregression15.php on line 220

Warning: Undefined variable $j in /var/www/html/ponce/onlineregression15.php on line 226

Warning: Undefined variable $trvar in /var/www/html/ponce/onlineregression15.php on line 227

Warning: Trying to access array offset on null in /var/www/html/ponce/onlineregression15.php on line 227
tr(1) =  .   

OUTPUT:

a =
Warning: Undefined variable $acoef in /var/www/html/ponce/onlineregression15.php on line 234

Deprecated: substr(): Passing null to parameter #1 ($string) of type string is deprecated in /var/www/html/ponce/onlineregression15.php on line 234
           b =
Warning: Undefined variable $bcoef in /var/www/html/ponce/onlineregression15.php on line 234

Deprecated: substr(): Passing null to parameter #1 ($string) of type string is deprecated in /var/www/html/ponce/onlineregression15.php on line 234

            

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Count 

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