UPDATE: Dump of initial files

base/src/functions/engineering/misc.rs

@@ -0,0 +1,59 @@
+use crate::{
+    calc_result::{CalcResult, CellReference},
+    expressions::parser::Node,
+    model::Model,
+    number_format::to_precision,
+};
+
+impl Model {
+    // DELTA(number1, [number2])
+    pub(crate) fn fn_delta(&mut self, args: &[Node], cell: CellReference) -> CalcResult {
+        let arg_count = args.len();
+        if !(1..=2).contains(&arg_count) {
+            return CalcResult::new_args_number_error(cell);
+        }
+        let number1 = match self.get_number_no_bools(&args[0], cell) {
+            Ok(f) => f,
+            Err(error) => return error,
+        };
+        let number2 = if arg_count > 1 {
+            match self.get_number_no_bools(&args[1], cell) {
+                Ok(f) => f,
+                Err(error) => return error,
+            }
+        } else {
+            0.0
+        };
+
+        if to_precision(number1, 16) == to_precision(number2, 16) {
+            CalcResult::Number(1.0)
+        } else {
+            CalcResult::Number(0.0)
+        }
+    }
+
+    // GESTEP(number, [step])
+    pub(crate) fn fn_gestep(&mut self, args: &[Node], cell: CellReference) -> CalcResult {
+        let arg_count = args.len();
+        if !(1..=2).contains(&arg_count) {
+            return CalcResult::new_args_number_error(cell);
+        }
+        let number = match self.get_number_no_bools(&args[0], cell) {
+            Ok(f) => f,
+            Err(error) => return error,
+        };
+        let step = if arg_count > 1 {
+            match self.get_number_no_bools(&args[1], cell) {
+                Ok(f) => f,
+                Err(error) => return error,
+            }
+        } else {
+            0.0
+        };
+        if to_precision(number, 16) >= to_precision(step, 16) {
+            CalcResult::Number(1.0)
+        } else {
+            CalcResult::Number(0.0)
+        }
+    }
+}