Index in position 2 exceeds array bounds. Index must not exceed 27.

I can't figure out why I am recieving an error message "Index in position 2 exceeds array bounds. Index must not exceed 27." when none of my INPUT matrices exceed 27 in position 2... INPUTS are made of zeros array to maintain the correct size of each array (other values are used in the actual code)

FINAL_OUTPUT = find_dbTP_Valley_Rim_JS(RFDB, unit_type, GIN_TEMPS_JS_STUCT, YYV_TEMPS_JS_STRUCT, YYV_PRECIP_JS)

%INPUTS
RFDB = zeros(1485,5)
unit_type = char('english')
GIN_TEMPS_JS_STUCT = struct;
    GIN_TEMPS_JS_STUCT.name ='GIN';
    GIN_TEMPS_JS_STUCT.elevation = 2149;
    GIN_TEMPS_JS_STUCT.hourly = zeros(13047,27); %double array of 13047 rows and 27 columns
YYV_TEMPS_JS_STRUCT = struct();
    YYV_TEMPS_JS_STRUCT.name ='YYV';
    YYV_TEMPS_JS_STRUCT.elevation = 2149;
    YYV_TEMPS_JS_STRUCT.hourly = zeros(80363,27); %double array of 80363 rows and 27 columns
YYV_PRECIP_JS = zeros(8046,27) %double array of 8046 rows and 27 columns
elev_rim = 2377;    % 7800'; 
elev_valley = 1280; % 4200';

%FINAL CODE
S = size(RFDB);
L = S(1);
for i = 1:L
    cur = RFDB(i, :);
    
    year = cur(2);
    month = cur(3);
    day = cur(4);
    time = cur(5);
    
    if day == 0
        % change the # of -100 depending on find_temp output length
        RF_RIM_TEMPS = [-100, -100, -100, -100, 0];
        RF_YYV_TEMPS = [-100, -100, -100, -100, 0];
        RF_YYV_PRECIPS = [-100, -100, -100, -100];
        
        RFDB(i, :) = [cur, RF_RIM_TEMPS, RF_YYV_TEMPS, RF_YYV_PRECIPS];
        continue   
    elseif time < 0
        time = 23/24;
    end
    
    date = datenum(year, month, day) + time;
    datestr(date);
    
    RF_RIM_TEMPS = find_temp_JS(date, unit_type, elev_rim, GIN_TEMPS_JS_STUCT);
    RF_YYV_TEMPS = find_temp_JS(date, unit_type, elev_valley, YYV_TEMPS_JS_STRUCT);
    YYV_RF_Precip = find_precip_JS(date, unit_type, YYV_PRECIP_JS);
    JS_TP(i, :) = [cur, RF_RIM_TEMPS, RF_YYV_TEMPS, YYV_RF_Precip];
    % Final OUTPUT^^ 

Note: Two codes shown below find_precip_JS and find_temp_JS are used within the final code "find_dbTP_Valley_Rim_JS"

1 of 2 Codes Used in Final Code: find_precip_JS

    function[out_data] = find_precip_JS(date, unit_type, YYV_PRECIP_JS)
%% The objective is to find the precipitation of at the time of the rockfall
% 
% out_data = find_precip(date, unit_type, precip_data)
% 
% Inputs:
%   precip data = [year, month, day, P_12am, P_1am, ..., P_11pm]
%   unit_type = 'metric' for precip in centimeters
%
% out_data = [yearly cumulative, last 30 days, last 72 hours, last 24 hours]
%   
%
% Requirements: Precip DATA FILE ASSUMED TO BE WELL-BEHAVED! No erroneous
% points
% 
% ** Also, past 24 and past 72 hours may give bad data if the rock fall
% occurs on July 1, 2, or 3 AND it was raining (Data is set to zero).
% 
%% Collect the data for the appropriate day
day = floor(date);
time = round((date-day)*24);
time_ind = 4 + time;
hourly = YYV_PRECIP_JS;
pyear = hourly(:, 1);
pmonth = hourly(:, 2);
pday = hourly(:, 3);
p_days = datenum(pyear, pmonth, pday);
ind = find(p_days == day);
if isempty(ind)
    out_data = [-100, -100, -100, -100];
    return
end
p_now = hourly(ind, time_ind); % rainfall now
p_yest = hourly(ind-1, time_ind); % rain at this time yesterday
p_24 = p_now - p_yest; % 24 hour rainfall
p_minus3 = hourly(ind-3, time_ind); % rain at this time 72 hrs ago
p_72 = p_now - p_minus3; % 72 hour rainfall
% sets data to zero if negative (will occur with good data on July 1
% (2, 3)), but this is wrong IF it was raining
if p_24 < 0
    p_24 = 0;
end
if p_72 < 0
    p_72 = 0;
end
dv = datevec(date);
%ind
if dv(2) == 7 %dv(2) is the month of the rf
    % Code assumes a very well-behaved data file
    dom = dv(3); % day of month
    July1_ind = ind-dom+1;
    
    %datestr(p_days(July1_ind))
    pm1 = hourly(July1_ind, 4); %rainfall, july start -> should be ZERO!
    
    %datestr(p_days(July1_ind-1))
    pm2 = hourly(July1_ind-1, 4); %rainfall, june30
    
    %datestr(p_days(ind-30))
    pm3 = hourly(ind-30, 4);
    
    p30a = p_now - pm1;
    p30b = pm2 - pm3;
    p_30 = p30a + p30b;
    
else
    p_month = hourly(ind - 30, 4);
    p_30 = p_now - p_month;
end
out_data = [p_now, p_30, p_72, p_24];
% convert to centimeters?
if strcmpi(unit_type,'metric')
    out_data = out_data * 2.54;
end

2 of 2 Codes Used in Final Code: find_temp_JS

function[out_data] = find_temp_JS(date, unit_type, elev_valley, YYV_TEMPS_JS_STRUCT)
% Inputs:
%  - date = matlab datenum
%  - elevation = elevation, in meters, for which you desire temperature
%  corrections
%  - unit_type = 'metric' for celcius units 'english' for fahrenheit
%  - YYV_TEMPS_JS_STRUCT or GIN_TEMPS_JS_STUCT= structure of temperature data, including:
%       name = 'Weather Station Name'
%       hourly = [year, month, day, T_12am, T_1am, ..., T_11pm]
%       daily = [datenum, max, min, avg]
%       elevation (in meters)
%       days = list of datenums of all days in db
%
% out_data = [min, avg, max, temp at rock fall, # stations contributing data]
%% Constants
t_grad = 0.0;
%% Collect the data for the appropriate day
day = floor(date);
time = round((date-day)*24);
time_ind = 4 + time;
hour = [time+1:1:23, 0:1:time];
L = length(YYV_TEMPS_JS_STRUCT)
cur = [];
k = 1;
for i = 1:L
    
    t_all = [];
    hourly = YYV_TEMPS_JS_STRUCT(i).hourly
    t_days = datenum(hourly(:, 1), hourly(:, 2), hourly(:, 3));
    
    ind = find(t_days == floor(date));
    
    
    % Create array of temps in the 24 hours prior to the rf (previous
    % hi/lo)
    
    if time_ind < 27
        t_today = hourly(ind, 4:time_ind);
        t_yesterday = hourly(ind-1, time_ind+1:27);
        t_all = [t_yesterday t_today];
        %t_h = [time-23:1:time];
    else
        %t_h = [0:1:23];
        t_all = hourly(ind, 4:27);
    end
    
    %t_all
    ind2 = t_all > -30;
    t_all = t_all(ind2);
    ind2 = t_all < 120;
    t_all = t_all(ind2);
    
    if isempty(t_all)
        continue
        % Do Nothing
    else
        %t_all
        YYV_TEMPS_JS_STRUCT(i).name;
        cur(k).t_max = max(t_all);
        cur(k).t_min = min(t_all);
        cur(k).t_avg = mean(t_all);
        cur(k).elevation = YYV_TEMPS_JS_STRUCT(i).elevation;
    end
    
    %% Find the temperature nearest to the time of the rock fall
    
    if time == 23  % this is a fake time, not appropriate for the rock fall
        time = 21; % 7pm is a neutral time
        time_ind = 4 + time;
    end
    
    
    % Create an array of the X hours surrounding the rock fall 
    
    plusminus = 6; % plusminus hours before and plusminus hours after 
    %time_ind
    if time_ind > 27 - plusminus % late in the day
        t_today = hourly(ind, time_ind-plusminus:27);
        offset = plusminus - (27 - time_ind) - 1;
        t_tomorw = hourly(ind+1, 4:4+offset);
        t_near = [t_today t_tomorw];
    elseif time_ind < 4 + plusminus % early in the day
        t_today = hourly(ind, 4:time_ind+plusminus);
        offset = plusminus - (time_ind - 4) - 1;
        t_yesrdy = hourly(ind-1, 27-offset:27);
        t_near = [t_yesrdy t_today];
    else
        t_near = hourly(ind, time_ind-plusminus:time_ind+plusminus);
    end
    
    t_h = [plusminus*-1:1:plusminus];
    
    ind3 = t_near > -30;
    t_near = t_near(ind3);
    t_h = t_h(ind3);
    ind3 = t_near < 120;
    t_near = t_near(ind3);
    t_h = t_h(ind3);
    
    n_ind = find(t_h == 0);
    
    % No data for time of rock fall
    if isempty(t_near)
        cur(k).t_rf = -100; % no data within plusminus hours of the rock fall
        
        % Exact data not available, but before and after data are available    
    elseif isempty(n_ind)
        b_ind = find(t_h < 0, 1, 'last');
        a_ind = find(t_h > 0, 1, 'first');
        
        % No before data: check to see if after data is close
        close = 4; % Close is defined as less than "close" hours
        if isempty(b_ind)
            if t_h(a_ind) < close;
                cur(k).t_rf = t_near(a_ind);
            else
                cur(k).t_rf = -100;
            end
            
            % No after data: check to see if before data is close    
        elseif isempty(a_ind)
            if t_h(b_ind) > -1 * close
                cur(k).t_rf = t_near(b_ind);
            else 
                cur(k).t_rf = -100;
            end
            
            % Both before and after data: linear extrapolation    
        else  
            span = t_h(a_ind) - t_h(b_ind); % hours between before and after 
            temp_span = t_near(a_ind) - t_near(b_ind);
            hr_incre = temp_span/span;
            t_rf_tmp = t_near(b_ind) + (hr_incre * (t_h(b_ind)*-1));
            cur(k).t_rf = t_rf_tmp;
        end
    else
        cur(k).t_rf = t_near(n_ind); % exact data available, use it!
    end
    k = k + 1;
end
%% Evaluate the temperature at the appropriate elevation
if isempty(cur)
    out_data = [-100, -100, -100, -100 0];
    return
else
    num_stat = length(cur);
end
%% It is possible to have min/max/avg data BUT NO temp at time of rock fall data
m = 1;
t_rf = -100;
for j = 1:num_stat
    t_elev = cur(j).elevation;
    t_diff = ((t_elev - elev)/100) * t_grad;
    t_max(j) = (cur(j).t_max + t_diff);
    t_min(j) = (cur(j).t_min + t_diff);
    t_avg(j) = (cur(j).t_avg + t_diff);
    t_rf_tmp = cur(j).t_rf;
    if t_rf_tmp == -100
        % Do nothing
    else
        t_rf(m) = (t_rf_tmp + t_diff);
        m = m + 1;
    end
end

[Stephen23]

@John Stapke: please show us the complete error message. This means all of the red text.

[John Stapke]

Index in position 2 exceeds array bounds. Index must not exceed 27.

Error in find_precip_JS (line 38)

p_now = hourly(ind, time_ind); % rainfall now

Error in find_dbTP_Valley_Rim_JS (line 56)

YYV_RF_Precip = find_precip_JS(date, unit_type, YYV_PRECIP_JS);

[Stephen23]

I don't see anything in the code of find_precip_JS that limits the value of time_ind to 27 or less.

You should check the size of hourly and time_ind using the debugging tools. If you have not used the debugging tools then this is the perfect time to start. The most useful command to begin is

dbstop if error

and then simply check the array size and index value. Let us know what the index value is.

Answer 1

[Cris LaPierre]

Somewhere in your code, you have a matrix of nx27, but in your code, you are trying to access a column > 27.

a=rand(3,27);
% Works
a(2,20)

ans = 0.3973

% Your error
a(2,28)

Index in position 2 exceeds array bounds. Index must not exceed 27.

If you look at the full error message, it will tell you what line of code is giving this error.