Unrecognized function or variable

Hi, I want to develop future IDF curve using equidistant quantile matching. I used the following codes. I don't understand why I received the error message ' unrecognized function or variable 'data-hist'? Can anyone please help me? Thanks in advance.

% Fitting Gumbel Distribution
% Negative sign for Gumbel distribution
% Positive is for minimums for evfit
IDF = zeros(size(data_hist,2),length(P));
hist_error = zeros(size(data_hist,2),length(P));
future_change1 = zeros(size(data_hist,2),length(P));
future_change2 = zeros(size(data_hist,2),length(P));
IDF_gen = zeros(size(data_hist,2),length(P));
IDF_gen1 = zeros(size(data_hist,2),length(P));
IDF_gen2 = zeros(size(data_hist,2),length(P));
IDF_gen3 = zeros(size(data_hist,2),length(P));
mtrA = zeros(size(data_hist,2), 4);
mtrPar = zeros(size(data_hist,2), 6);
for i = 1:size(data_hist,2)
 max_hist_con = data_hist(:,i);

[Rik]

Where do you define it as a variable? Where do you assign it a value?

[Pwint Oo San]

To be honest, I don't understand you question. The data are imorted into the wokspace well. When I run the following code in command window.

% Load Input Data
% Includes: Sub-daily Maximums, GCM base period daily maximum, GCM future
% period daily maximum
load input_data
% Sub-daily Time Interval
subdaily = [5,10,15,30,60,120,360,720,1440];
% Return Period
RT = [2,5,10,25,50,100];
P = 1./RT;

This is my workspace.

[Rik]

Where is data_hist?

As a side-note, you should not use load this way. It may overwrite variables without warning and it doesn't leave a trace what variables are loaded. Use something like this instead:

% Load Input Data
% Includes: Sub-daily Maximums, GCM base period daily maximum, GCM future
% period daily maximum
S=load('input_data.mat');
histSubDailyMaximums=S.histSubDailyMaximums;
GCMbaseperioddailymaximums=S.GCMbaseperioddailymaximums;
GCMfutureperioddailymaximums=S.GCMfutureperioddailymaximums;

% Sub-daily Time Interval
subdaily = [5,10,15,30,60,120,360,720,1440];
% Return Period
RT = [2,5,10,25,50,100];
P = 1./RT;