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## bug in peakflow?

 Dear JGrass developers,I have a question about the function h.peakflow.I have applied h.peakflow to a basin and I have considered a_idf=33.6, n_idf=0.49 and timestep=100 [s]. From the simulation one obtains that tpmax=88811secAs far as know, h.peakflow considers an event of a constant precipitation that lasts for tpmax. Using the rain curves, one should obtain a total rain of:33.6*(88811/3600)^0.49=161.62 [mm]I have opened the output file and I have summed all the values in the precipitation column (third column) obtaining:sum(output[,3]) 143.5201which is less than 161.62 [mm].I have looked to the code and, as far as I understand, the third column is calculated in the file QStatistic.java:Q[j] = h;The variable h is calculated in the file StatisticJeff.java at the line 87:double h = a_idf * Math.pow(tpmax / 3600.0, n_idf)/1000;where tpmax is the precipitation time, and a_idf and n_idf are the parameters of the rain curves. I think this is not correct. In fact, this h represents the total height of precipitation fallen in tpmax and is expressed in meters [m]. It results in:> 33.6*(88811/3600)^0.49/1000 0.1616217In fact the third column of the output file is a series of  0.16162 until tpmax. According to the code, this would mean that a rain of 0.16 meters is fallen on the basin for a duration of tpmax which counts for 143.5 meters of rain!!!For this reason, I think the correct line should be:Q[j] = J*1000*t; // [mm]which represents rain fallen on the basin during the timestep given in input. J is correctly calculated as:double J = a_idf * Math.pow(tpmax / 3600.0, n_idf - 1) / (1000.0 * 3600.0); // [m/s]In this case one would obtain in the output file a series of 0.1819839 [mm] which, multiplied by (88811/100) gives exactly 161.62 [mm] of rain.Another thing I would like to ask refers to the name Jeff: to me Jeff sounds like "effective rainfall intensity". However in the code the rain is given all in input, i.e. Jeff is equal to J.Is maybe the name misleading?Thanks in advance,Matteo Dall'Amico_______________________________________________ JGrass-users mailing list [hidden email] https://dev.fsc.bz.it/cgi-bin/mailman/listinfo/jgrass-users