X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=core%2Fsrc%2Fde%2Fcongrace%2Fexp4j%2FCommandlineInterpreter.java;fp=core%2Fsrc%2Fde%2Fcongrace%2Fexp4j%2FCommandlineInterpreter.java;h=78670a4277b36f2e8a20c6f06b6a26fa57825535;hb=9349577cdfdff682b2aabd6daa24fdc3a7449b58;hp=0000000000000000000000000000000000000000;hpb=30ba0a882f0c061176ba14dbf86d3d6fad096c02;p=debian%2Fopenrocket

diff --git a/core/src/de/congrace/exp4j/CommandlineInterpreter.java b/core/src/de/congrace/exp4j/CommandlineInterpreter.java
new file mode 100644
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+++ b/core/src/de/congrace/exp4j/CommandlineInterpreter.java
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+/*
+   Copyright 2011 frank asseg
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+
+ */
+package de.congrace.exp4j;
+
+/**
+ * Simple commandline interpreter for mathematical expressions the interpreter
+ * takes a mathematical expressions as a {@link String} argument, evaluates it
+ * and prints out the result.
+ * 
+ * 
+ * <pre>
+ * java de.congrace.exp4j.CommandlineInterpreter "2 * log(2.2223) - ((2-3.221) * 14.232^2)"
+ * > 248.91042049521056
+ * </pre>
+ * 
+ * @author fas@congrace.de
+ * 
+ */
+public class CommandlineInterpreter {
+	private static void calculateExpression(String string) {
+		try {
+			final PostfixExpression pe = PostfixExpression.fromInfix(string);
+			System.out.println(pe.calculate());
+		} catch (UnparsableExpressionException e) {
+			e.printStackTrace();
+		} catch (UnknownFunctionException e) {
+			e.printStackTrace();
+		}
+	}
+
+	public static void main(String[] args) {
+		if (args.length != 1) {
+			printUsage();
+		} else {
+			calculateExpression(args[0]);
+		}
+	}
+
+	private static void printUsage() {
+		final StringBuilder usage = new StringBuilder();
+		usage.append("Commandline Expression Parser\n\n").append("Example: ").append("\n").append("java -jar exp4j.jar \"2.12 * log(23) * (12 - 4)\"\n\n")
+				.append("written by fas@congrace.de");
+		System.err.println(usage.toString());
+	}
+}