FIX: Adds documentation

xlsx/examples/hello_calc.rs

@@ -0,0 +1,28 @@
+use ironcalc::{
+    base::{expressions::utils::number_to_column, model::Model},
+    export::save_to_xlsx,
+};
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let mut model = Model::new_empty("hello-calc.xlsx", "en", "UTC")?;
+    // Adds a square of numbers in the first sheet
+    for row in 1..100 {
+        for column in 1..100 {
+            let value = row * column;
+            model.set_user_input(0, row, column, format!("{}", value));
+        }
+    }
+    // Adds a new sheet
+    model.add_sheet("Calculation")?;
+    // column 100 is CV
+    let last_column = number_to_column(100).unwrap();
+    let formula = format!("=SUM(Sheet1!A1:{}100)", last_column);
+    model.set_user_input(1, 1, 1, formula);
+
+    // evaluates
+    model.evaluate();
+
+    // saves to disk
+    save_to_xlsx(&model, "hello-calc.xlsx")?;
+    Ok(())
+}