summaryrefslogtreecommitdiff
path: root/nuttx/lib/math/lib_b16cos.c
diff options
context:
space:
mode:
Diffstat (limited to 'nuttx/lib/math/lib_b16cos.c')
-rw-r--r--nuttx/lib/math/lib_b16cos.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/nuttx/lib/math/lib_b16cos.c b/nuttx/lib/math/lib_b16cos.c
new file mode 100644
index 000000000..69cc61042
--- /dev/null
+++ b/nuttx/lib/math/lib_b16cos.c
@@ -0,0 +1,64 @@
+/****************************************************************************
+ * lib/math/lib_b16cos.c
+ *
+ * Copyright (C) 2007, 2008, 2011 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <fixedmath.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: b16cos
+ ****************************************************************************/
+
+b16_t b16cos(b16_t rad)
+{
+ /* Compute cosine: sin(rad + PI/2) = cos(rad) */
+
+ rad += b16HALFPI;
+ if (rad > b16PI)
+ {
+ rad -= b16TWOPI;
+ }
+ return b16sin(rad);
+}