1 files changed, 169 insertions, 0 deletions
diff --git a/plugin_math.c b/plugin_math.c
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+/* $Id: plugin_math.c 840 2007-09-09 12:17:42Z michael $
+ * $URL: https://ssl.bulix.org/svn/lcd4linux/trunk/plugin_math.c $
+ *
+ * math plugin
+ *
+ * Copyright (C) 2003 Michael Reinelt <michael@reinelt.co.at>
+ * Copyright (C) 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
+ *
+ * This file is part of LCD4Linux.
+ *
+ * LCD4Linux is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * LCD4Linux is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+/* 
+ * exported functions:
+ *
+ * int plugin_init_math (void)
+ *  adds some handy constants and functions
+ *
+ */
+
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+
+#include "debug.h"
+#include "plugin.h"
+
+
+static void my_sqrt(RESULT * result, RESULT * arg1)
+{
+    double value = sqrt(R2N(arg1));
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_exp(RESULT * result, RESULT * arg1)
+{
+    double value = exp(R2N(arg1));
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_ln(RESULT * result, RESULT * arg1)
+{
+    double value = log(R2N(arg1));
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_log(RESULT * result, RESULT * arg1)
+{
+    double value = log10(R2N(arg1));
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_sin(RESULT * result, RESULT * arg1)
+{
+    double value = sin(R2N(arg1));
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_cos(RESULT * result, RESULT * arg1)
+{
+    double value = cos(R2N(arg1));
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_tan(RESULT * result, RESULT * arg1)
+{
+    double value = tan(R2N(arg1));
+    SetResult(&result, R_NUMBER, &value);
+}
+
+
+static void my_min(RESULT * result, RESULT * arg1, RESULT * arg2)
+{
+    double a1 = R2N(arg1);
+    double a2 = R2N(arg2);
+    double value = a1 < a2 ? a1 : a2;
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_max(RESULT * result, RESULT * arg1, RESULT * arg2)
+{
+    double a1 = R2N(arg1);
+    double a2 = R2N(arg2);
+    double value = a1 > a2 ? a1 : a2;
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_floor(RESULT * result, RESULT * arg)
+{
+    double value = floor(R2N(arg));
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_ceil(RESULT * result, RESULT * arg)
+{
+    double value = ceil(R2N(arg));
+    SetResult(&result, R_NUMBER, &value);
+}
+
+static void my_decode(RESULT * result, int argc, RESULT * argv[])
+{
+    int index;
+
+    if (argc < 2) {
+	error("decode(): wrong number of parameters");
+	SetResult(&result, R_STRING, "");
+	return;
+    }
+
+    index = R2N(argv[0]);
+
+    if (index < 0 || index >= argc - 1) {
+	SetResult(&result, R_STRING, "");
+	return;
+    }
+
+    CopyResult(&result, argv[index + 1]);
+}
+
+
+int plugin_init_math(void)
+{
+    /* set some handy constants */
+    SetVariableNumeric("Pi", M_PI);
+    SetVariableNumeric("e", M_E);
+
+    /* register some basic math functions */
+    AddFunction("sqrt", 1, my_sqrt);
+    AddFunction("exp", 1, my_exp);
+    AddFunction("ln", 1, my_ln);
+    AddFunction("log", 1, my_log);
+    AddFunction("sin", 1, my_sin);
+    AddFunction("cos", 1, my_cos);
+    AddFunction("tan", 1, my_tan);
+
+    /* min, max */
+    AddFunction("min", 2, my_min);
+    AddFunction("max", 2, my_max);
+
+    /* floor, ceil */
+    AddFunction("floor", 1, my_floor);
+    AddFunction("ceil", 1, my_ceil);
+
+    /* decode */
+    AddFunction("decode", -1, my_decode);
+
+    return 0;
+}
+
+void plugin_exit_math(void)
+{
+}