MagicPlot Manual

Plotting and nonlinear fitting software

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integration [Sat Jun 26 21:45:36 2010]
Alexander
integration [Thu Jan 14 17:20:17 2021] (current)
Alexander
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-====== Integration (Pro edition only) ===== +====== Integration ===== 
-Open Table or Figure or Plot with initial data and use ''Processing -> Integrate'' menu item.+Open Table or Figure or Fit Plot with initial data and select ''Processing -> Integrate'' menu item.
  
-{{:integr1.png|Integrate table columns dialog}} | {{:integr2.png|Integrate curve dialog}} |+{{:integrate.png?nolink|}}
  
 ===== Baseline Correction ===== ===== Baseline Correction =====
-If your initial data to be integrated contains a baseline (usually constant or linear), you might to subtract it from data **before** integrating. The constant baseline will result in linearly growing integral. +If your initial data to be integrated contains a baseline (usually constant or linear), you may want to subtract it from data **before** integrating. (A constant baseline will result in linearly growing integral.
  
 In such case the algorithm may be the following: In such case the algorithm may be the following:
   - Create Fit Plot with your initial table data   - Create Fit Plot with your initial table data
-  - Add a Fit Curve which simulates the baseline. Usually it will be ''Line Fit Curve''. You may specify you own equation (**Pro** only) +  - Add a Fit Curve which simulates the baseline. You may specify a custom equation 
-  - Specify Fit Interval so that it does contain only noise points+  - Specify Fit Interval so that it contains only noise points
   - Fit the data by clicking ''Fit Sum'' button   - Fit the data by clicking ''Fit Sum'' button
-  - Subtract the baseline fitting curve from data by checking ''Baseline'' check box in curves list +  - Subtract the baseline fitting curve from data by checking ''Baseline'' checkbox in curves list 
-  - Use menu ''Processing → Integrate'' to integrate the data without baseline+  - Use menu ''Processing → Integrate'' to integrate the plotted data without baseline.
  
-===== Formula =====+===== Algorithm =====
 To perform integration you should specify two columns: //x// and //y//. Missing values are ignored. To perform integration you should specify two columns: //x// and //y//. Missing values are ignored.
  
 MagicPlot uses [[wp>Trapezoidal_rule|trapezoidal rule]] to compute the integral: MagicPlot uses [[wp>Trapezoidal_rule|trapezoidal rule]] to compute the integral:
  
-<m>I_n = sum{i=2}{n}{(x_i} − x_{i − 1}) {{y_i + y_{i − 1}} / 2},~ n=2...N;~~ I_1=0</m>+<m>I_n = 1/2 sum{i=2}{n}{(x_i} − x_{i − 1}) ({y_i + y_{i − 1})},~ n=2...N;~~ I_1=0</m>
  
 ===== See Also ===== ===== See Also =====
 +  * [[processing]]
   * [[Differentiation]]   * [[Differentiation]]
integration.1277574336.txt.gz · Last modified: Sun Nov 8 12:20:32 2015 (external edit)