DDF method gives negative r^2 values

[lyguy]

Using the one-point test dems and climate values and (this)[https://gist.github.com/8b95187b48e8d0f75bc0] input.dat, I get the following output:

MEAN MASS BALANCE OVER 0 YEARS (2001 - 2000)
  bw = nan   bs = nan   bn = nan
  number of grid cells of all elevation belts = 0
 years= 0  numberexcludeyears (years excluded from computing mb profiles =0

         r2 for discharge =-581.4510

 function r2calcln: ERROR in calculation of f02 (ln) i=1 j=1 --> division by 0!!

         logarithmic r2 =   0.0000

 number of glacier grids         1
 number of calculated time steps   3

 number of timesteps of dischargedata  4

  simulated discharge volume (100 000 m3) =     1.41
  measured discharge volume               =     0.11

Note the negative r2 value and the error thrown by the log r2 function.

[lyguy]

The calculates "r2" value is the Nash-Sutcliff model efficiency, and not the root-mean-squared-error. Nash-Sutcliff takes values from -∞ to 1. Closing as invalid.