1 files changed, 67 insertions, 0 deletions
diff --git a/dataSlice.sci b/dataSlice.sci
new file mode 100644
index 0000000..6b3c160
--- /dev/null
+++ b/dataSlice.sci
@@ -0,0 +1,67 @@
+function sys = dataSlice(data,Start,End,Freq)
+    [lhs,rhs] = argn()
+    // storing the model data 
+    modelData = data
+    // storing the statrting point
+    try
+        startData = Start
+    catch
+        startData = 1
+    end
+    //storing the end point
+    try 
+        endData = End
+    catch
+        endData = LastIndex(data)
+    end
+    //Storing the frequency
+    try
+        freqData = Freq
+    catch
+        freqData = 1
+    end
+    // error message generate
+    if startData > endData  then
+        error(msprintf(gettext("%s:Start index can not greater than End index.\n"),"dataSlice"))
+    end
+    if size(startData,'*') ~= 1 then
+        error(msprintf(gettext("%s:Start index must be non negative scalar integer number.\n"),"dataSlice"))
+    end
+    if size(endData,'*') ~= 1 then
+        error(msprintf(gettext("%s:End index must be non negative scalar integer number.\n"),"dataSlice"))
+    end
+    if ~freqData || size(freqData,'*') ~= 1 then
+        error(msprintf(gettext("%s:Frequency must be non negative scalar number.\n"),"dataSlice"))
+    end
+    //--------------------------------------------------------------------------
+    if typeof(modelData) == 'constant' then
+        Ts = 1
+    elseif typeof(modelData) == 'iddata' then
+        Ts = modelData.Ts
+    end
+    //--------------------------------------------------------------------------
+    if freqData> Ts || modulo(Ts,freqData) then
+        warning(msprintf(gettext("%s:inconsistent frequency.\n"),"dataSlice"))
+        freqData = Ts
+    end
+    if typeof(modelData) == 'constant' then
+        temp = modelData(startData:Ts/freqData:endData,:)
+    elseif typeof(modelData) == 'iddata' then
+        tempY = modelData.OutputData;tempU = modelData.InputData
+        tempY = tempY(startData:Ts/freqData:endData,:);tempU = tempU(startData:Ts/freqData:endData,:)
+        temp = iddata(tempY,tempU,Ts/freqData)
+        temp.TimeUnit = modelData.TimeUnit
+    end
+    sys = temp
+endfunction
+
+function varargout = LastIndex(modelData)
+    //finding the sample size
+    if typeof(modelData) == "constant" then
+        varargout(1) = length(modelData(:,1))
+        
+    elseif typeof(modelData) == "iddata"  then
+        temp = modelData.OutputData
+        varargout(1) = length(temp(:,1))
+    end    
+endfunction