Plot or integrate using file spreadsheet data

Use the "Var=>▤Values=>Read from Sheet" option to open the variable editor. Then read from a spreadsheet file using the "Read Create Spreadsheet..." option. After the file is read by the app, a page is displayed showing the variable names from 'A' to 'Z' where each variable is mapped to a specific column. 

If required, change the default mappings. You may specifically want to change mapping for an independent variable like X to point to a column having independent values. This column can be used as a reference to plot or integrate. (Skip this step if there is no independent variable for example in case of sequential data)

By default, Variable X is mapped to 1st column. Y is mapped to 2nd column. To plot or integrate 2nd column data in file with respect to 1st column, simply input the expression Y and tap on 📈 or ≈∫ and select independent variable as X. 

The data/rows will be automatically sorted with respect to X column by the app. If you do not need any sorting for example in case of sequential data without an independent variable, select SEQ_NO as independent variable.

You can also use any complex expression that operates over the file data. For example, to plot the rate of change of Y with respect to X, use the expression derv(1, Y, X) using "Var" option on main screen. This will plot ∂/∂X(Y) i.e. rate of change of Y (Col 2) with respect to X (Col 1).



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