From 54bb80251432ff49c967115f8401e7dafc5c57d6 Mon Sep 17 00:00:00 2001
From: Thales Lima Oliveira <thaleslima.ufu@gmail.com>
Date: Tue, 19 Dec 2017 22:00:05 -0200
Subject: Several implementations on math expression block

---
 Project/fparser/examples/example2.cc | 85 ++++++++++++++++++++++++++++++++++++
 1 file changed, 85 insertions(+)
 create mode 100644 Project/fparser/examples/example2.cc

(limited to 'Project/fparser/examples/example2.cc')

diff --git a/Project/fparser/examples/example2.cc b/Project/fparser/examples/example2.cc
new file mode 100644
index 0000000..958b9a1
--- /dev/null
+++ b/Project/fparser/examples/example2.cc
@@ -0,0 +1,85 @@
+// Simple example file for the function parser
+// ===========================================
+/* Note that the library has to be compiled with
+   FP_SUPPORT_FLOAT_TYPE, FP_SUPPORT_LONG_DOUBLE_TYPE and
+   FP_SUPPORT_LONG_INT_TYPE
+   preprocessor macros defined for this example to work.
+
+   Try with these input values with the different floating point parser
+   types to see the difference in accuracy:
+
+f(x) = x + 1.234567890123456789
+min x: 0
+max x: 2
+step: 1
+*/
+
+#include "../fparser.hh"
+
+#include <iostream>
+#include <iomanip>
+#include <string>
+
+template<typename Parser>
+void runExample(const char* valueTypeName)
+{
+    typedef typename Parser::value_type Value_t;
+
+    std::cout << "Using " << valueTypeName << " parser." << std::endl;
+
+    Parser fparser;
+    std::string function;
+    Value_t minx, maxx, step;
+
+    fparser.AddConstant("pi", Value_t(3.1415926535897932));
+
+    std::cin.ignore();
+    while(true)
+    {
+        std::cout << "f(x) = ";
+        std::getline(std::cin, function);
+        if(std::cin.fail()) return;
+
+        int res = fparser.Parse(function, "x");
+        if(res < 0) break;
+
+        std::cout << std::string(res+7, ' ') << "^\n"
+                  << fparser.ErrorMsg() << "\n\n";
+    }
+
+    std::cout << "min x: ";
+    std::cin >> minx;
+    std::cout << "max x: ";
+    std::cin >> maxx;
+    std::cout << "step: ";
+    std::cin >> step;
+    if(std::cin.fail()) return;
+
+    Value_t vals[] = { 0 };
+    for(vals[0] = minx; vals[0] <= maxx; vals[0] += step)
+    {
+        std::cout << std::setprecision(20);
+        std::cout << "f(" << vals[0] << ") = " << fparser.Eval(vals)
+                  << std::endl;
+    }
+}
+
+int main()
+{
+    int choice = 0;
+    do
+    {
+        std::cout << "1 = double, 2 = float, 3 = long double, 4 = long int: ";
+        std::cin >> choice;
+    } while(choice < 1 || choice > 4);
+
+    switch(choice)
+    {
+      case 1: runExample<FunctionParser>("double"); break;
+      case 2: runExample<FunctionParser_f>("float"); break;
+      case 3: runExample<FunctionParser_ld>("long double"); break;
+      case 4: runExample<FunctionParser_li>("long int"); break;
+    }
+
+    return 0;
+}
-- 
cgit